• Visit
    • Buy Tickets
    • Calendar
    • After Dark Thursdays
    • Exhibits
    • Artworks on View
    • Getting Here
    • Event Rentals
  • Education
    • Professional Development Programs
    • Tools for Teaching and Learning
    • Learning About Learning
    • Community Programs
    • Educator Newsletter
  • Explore
    • Browse by Subject
    • Activities
    • Video
    • Exhibits
    • Apps
    • Blogs
    • Websites
  • About Us
    • Our Story
    • Partnerships
    • Global Collaborations
    • Explore Our Reach
    • Arts at the Exploratorium
    • Contact Us
  • Join + Support
    • Donate today!
    • Membership
    • Join our donor community
    • Engage your business
    • Attend a fundraiser
    • Party at the Piers
    • Explore our reach
    • Thank you to our supporters
    • Host your event
    • Volunteer
  • Store
  • Visit
    • Buy Tickets
    • Frequently Asked Questions
    • Calendar
      • Today
      • This Week
      • After Dark Thursday Nights
      • Arts
      • Conferences
      • Cinema Arts
      • Free and Community Events
      • Fundraising Events
      • Kids + Families
      • Live Webcasts
      • Members
      • Ongoing + Series
      • Special Hours and Open Mondays
      • Private Event Closures
    • Hours
    • Getting Here
    • Museum Map
    • Reduced Rates & Community Day
    • Accessibility
    • Tips for Visiting with Kids
    • How to Exploratorium
    • Exhibits
    • Tactile Dome
    • Artworks on View
    • Cinema Arts
    • Kanbar Forum
    • Black Box
    • Museum Galleries
      • Bernard and Barbro Osher Gallery 1: Human Phenomena
        • Exhibition: Science of Sharing
          • Educator Activities
        • Tactile Dome
          • 1971 Press Release
        • Black Box
        • Curator Statement
      • Gallery 2: Tinkering
        • Curator Statement
      • Bechtel Gallery 3: Seeing and Listening
        • Curator Statement
      • Gallery 4: Living Systems
        • Curator Statement
      • Gallery 5: Outdoor Exhibits
        • Curator Statement
      • Fisher Bay Observatory Gallery 6: Observing Landscapes
        • Wired Pier Environmental Field Station
        • Curator Statement
      • PlayLists
        • All PlayLists
        • A Different Light
        • “We” or “Just Me”?
        • See Yourself in Cells
        • Greatest Hits: Gallery 2
        • Greatest Hits: Gallery 3
        • Greatest Hits: Gallery 4
        • Museum Map
    • Restaurant & Café
    • School Field Trips
      • Getting Here
        • Bus Routes for Field Trips and Other Groups
      • Prices and Discounts
      • Planning Guide
      • Reservations
        • Field Trip Request Form
      • Resources
    • Groups / Tour Operators
      • Group Visit Request Form
    • Event Rentals
      • COVID-Compliant Options
      • Full Facility & Gallery Bundles
      • Fisher Bay Observatory Gallery & Terrace
      • East Gallery
      • Bechtel Central Gallery
      • Osher West Gallery
      • Kanbar Forum

      • Weddings
      • Proms and School Events
      • Daytime Meetings & Events
      • Happy Hour on the Water

      • Rentals FAQ
      • Event Planning Resources
      • Rental Request Form
      • Download Brochure (pdf)
    • Exploratorium Store
    • Contact Us
    • Español
    • 繁體中文
    • 简体中文
    • 한국어
    • Français
    • Deutsch
    • Português
    • 日本語
  • Education
    • Black Teachers and Students Matter
    • Professional Development Programs
      • Teacher Institute
        • About the Teacher Institute
        • Summer Institute for Teachers
        • Teacher Induction Program
        • Leadership Program
        • Teacher Institute Research
        • CA NGSS STEM Conferences
          • NGSS STEM Conference 2020
        • Science Snacks
          • Browse by Subject
          • Special Collections
          • Science Snacks A-Z
          • NGSS Planning Tools
          • Frequently Asked Questions
        • Digital Teaching Boxes
        • Meet the Teacher Institute Staff
        • Resources for Supporting Science Teachers
      • Institute for Inquiry
        • What Is Inquiry?
        • Inquiry-based Science and English Language Development
          • Educators Guide
            • Conceptual Overview
              • Science Talk
              • Science Writing
            • Classroom Video Gallery
              • Magnet Investigation
              • Snail Investigation
            • Teacher Professional Development
            • Project Studies
            • Acknowledgments
          • Conference: Exploring Science and English Language Development
            • Interviews with Participants
            • Plenary Sessions
            • Synthesis, Documentation, and Resources
        • Workshops
          • Participant Portal
          • Fundamentals of Inquiry
            • Summary Schedule
          • BaySci Science Champions Academy
          • Facilitators Guides
          • Commissioned Workshops
        • Resource Library
        • Meet the IFI Staff
      • Resources for California Educators
      • K-12 Science Leader Network
      • Resources for Supporting Science Teachers
      • Field Trip Explainer Program
    • Tools for Teaching and Learning
      • Learning Toolbox
      • Science Snacks
      • Digital Teaching Boxes
      • Science Activities
      • Tinkering Projects
      • Recursos gratuitos para aprender ciencias
      • Videos
      • Exhibits
      • Publications
      • Apps
      • Educator Newsletter
      • Exploratorium Websites
    • Educator Newsletter
    • Advancing Ideas about Learning
      • Visitor Research and Evaluation
        • What we do
        • Reports & Publications
        • Projects
        • Who we are
      • Center for Informal Learning in Schools
    • Community Programs
      • High School Explainer Program
      • Xtech
      • Community Educational Engagement
      • California Tinkering Afterschool Network
        • About
        • Partners
        • Resources
        • News & Updates
        • Further Reading
  • Explore
    • Browse by Subject
      • Arts
      • Astronomy & Space Sciences
        • Planetary Science
        • Space Exploration
      • Biology
        • Anatomy & Physiology
        • Ecology
        • Evolution
        • Genetics
        • Molecular & Cellular Biology
        • Neuroscience
      • Chemistry
        • Combining Matter
        • Food & Cooking
        • Materials & Matter
        • States of Matter
      • Data
        • Data Collection & Analysis
        • Modeling & Simulations
        • Visualization
      • Earth Science
        • Atmosphere
        • Geology
        • Oceans & Water
      • Engineering & Technology
        • Design & Tinkering
        • Real-World Problems & Solutions
      • Environmental Science
        • Global Systems & Cycles
        • Human Impacts
      • History
      • Mathematics
      • Nature of Science
        • Measurement
        • Science as a Process
        • Size & Scale
        • Time
      • Perception
        • Light, Color & Seeing
        • Listening & Hearing
        • Optical Illusions
        • Scent, Smell & Taste
        • Tactile & Touch
      • Physics
        • Electricity & Magnetism
        • Energy
        • Heat & Temperature
        • Light
        • Mechanics
        • Quantum
        • Sound
        • Waves
      • Social Science
        • Culture
        • Language
        • Psychology
        • Sociology
    • Browse by Content Type
      • Activities
      • Blogs
      • Exhibits
      • Video
      • Websites
      • Apps
        • Total Solar Eclipse
  • About Us
    • Our Story
    • Explore Our Reach
    • Impact Report
    • Fact Sheet
    • Awards
    • Our History
      • 50 Years 1969–2019

    • Senior Leadership
    • Board of Trustees
    • Board of Trustees Alumni
    • Staff Scientists
    • Staff Artists

    • Arts at the Exploratorium
      • Artworks on View
      • Artist-in-Residence Program
      • Cinema Arts
        • History and Collection
        • Cinema Artists-in-Residence
        • Resources and Collaborating Organizations
        • Kanbar Forum
      • Center for Art & Inquiry
        • Begin Here
          • Lessons
            • Bob Miller/Light Walk
            • Ruth Asawa/Milk Carton Sculpture
          • Workshops
      • Resonance
        • About the Series
        • See & Hear
        • Past Seasons
      • Over the Water
      • Black Box
      • Upcoming Events
      • Temporary Exhibitions
      • Arts Program Staff
      • Arts Committee and Advisers
    • Teacher Institute
    • Institute for Inquiry
    • Online Engagement
    • Explainer Programs
    • Studio for Public Spaces
    • Exhibit Making
    • Partnerships
      • Building Global Connections
        • Global Collaborations
          • Projects
          • Approach
          • People
          • Impact
      • Partnering with Science Agencies
        • NASA
        • NOAA
      • Partnering with Educational Institutions
      • Osher Fellows

    • Job Opportunities
    • Become a Volunteer

    • Contact Info
    • Newsletter
    • Educator Newsletter
    • Blogs
    • Follow & Share
    • Press Office

    • FY20 Audit Report
    • 990 FY19 Tax Return
    • Use Policy
      • Privacy Policy
      • Intellectual Property Policy
  • Join + Support
    • Donate today!
    • Membership
      • Membership FAQ
      • Member Benefits
      • After Dark Membership
      • Member Events
      • May Is for Members
    • Join our donor community
    • Engage your business
      • Corporate Membership
      • Luminary Partnerships
    • Attend a fundraiser
      • Wonder Funday
      • Science of Cocktails
      • Party at the Piers
        • Event Leadership and Host Committee
    • Explore our reach
    • Thank you to our supporters
    • Volunteer
      • Benefits
      • How to Apply
      • Application for Corporate Groups
      • Application for Internships
      • Application for Professional Societies
      • Application for School Groups & Clubs
      • Our Contract
      • Application for Individuals
      • Opportunities
  • Press Office
    • Press Releases
    • News Coverage
    • Events Calendar
    • Fact Sheet
    • Photographs
    • Press Video
    • Press Kits
    • Press Visits
    • Exploratorium Logos
    • Recent Awards
    • Praise for the Exploratorium
    • Join Our Press List
  • Store
 

Learn with us online while the Exploratorium is temporarily closed. You can help us reopen—donate today.

Exploratorium
Exploratorium
  • Visit
    • Buy Tickets
    • Calendar
    • After Dark Thursdays
    • Exhibits
    • Artworks on View
    • Getting Here
    • Event Rentals
  • Education
    • Professional Development Programs
    • Tools for Teaching and Learning
    • Learning About Learning
    • Community Programs
    • Educator Newsletter
  • Explore
    • Browse by Subject
    • Activities
    • Video
    • Exhibits
    • Apps
    • Blogs
    • Websites
  • About Us
    • Our Story
    • Partnerships
    • Global Collaborations
    • Explore Our Reach
    • Arts at the Exploratorium
    • Contact Us
  • Join + Support
    • Donate today!
    • Membership
    • Join our donor community
    • Engage your business
    • Attend a fundraiser
    • Party at the Piers
    • Explore our reach
    • Thank you to our supporters
    • Host your event
    • Volunteer
  • Store
Science Snacks

Snacks from A-Z


 A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z    See all

 

Science activity to make Earth's atmosphere to scale
A Little Atmosphere

Use a little bit of math to make a bonus accessory for your globe of the earth—an atmosphere, to scale.

Science activity to investigate the color of water
A Splash of Color

What color is water? Look through a clear tube to find out.

Science activity that demonstrates the afterimage phenomenon
Afterimage

After looking at something bright, such as a lamp or a camera flash, you may continue to see an image of that object when you look away. This lingering visual impression is called an afterimage.

Science activity demonstrating diffusion in cells
Agar Cell Diffusion

Use cubes of agar to model how diffusion occurs in cells. By observing cubes of different sizes, you can discover why larger cells might need extra help to transport materials.

Science activity that demonstrates the chemistry of batteries
Aluminum-Air Battery

Use aluminum foil, salt water, and activated charcoal to construct a simple battery strong enough to power a small motor or light.

Science activity to construct a cube that can be perceived in two ways
Ambiguous Cube

“Ambiguous” objects provide visual input that your brain can interpret in more than one way. With this Snack, you can make an ambiguous three-dimensional cube from drinking straws.

Science activity in which short pieces of chenille stem look random until viewed in the proper perspective
Ames Chair

Short pieces of chenille stem inside a box look like a random jumble, but when viewed in the proper perspective, and without normal depth perception, they look like a chair!

Anti-Gravity Mirror

A reflection of your right side can appear to be your left side. Try this activity and you'll appear to perform many gravity-defying stunts.

Science activity that explores how waves travel and interact
Anti-Sound Spring

In this simple exploration, a coiled phone cord slows the motion of a wave so you can see how a single pulse travels and what happens when two traveling wave pulses meet in the middle.

Science activity to make a model of your immune system
Antibody Attack

Explore how your immune system seeks out and disables pathogens, and prepares your body for future attacks.

Aporrea una pila

Una simple pila de bloques de madera demuestra que un objeto en reposo permanecerá en reposo al menos que una fuerza haga que se mueva.

Arpa de cabeza

Envuelve una cuerda alrededor de tu cabeza y púlsala para hacer música.

Science activity that demonstrates the angle of repose
Avalanche

What starts out as a cascade of well-mixed granular materials sorts itself into alternating layers of salt and sand.

A science activity to discover the diversity of insect life in your neighborhood
Backyard Bug Bonanza

You may think that hunting for insects requires a trip to the Amazon, but they’re everywhere on our planet. Where do you think you’ll find the greatest diversity of insects in your neighborhood?

Science activity that explores how yogurt is made
Bacteria Culture Club

Yogurt is the byproduct of hungry bacteria that digest the lactose in milk. You can make more yogurt just by feeding the bacteria more milk.

Science Activity to investigate microorganisms
Bacteriopolis

Make a living artwork that reveals the colorful microorganisms that live in the soil underfoot.

Science activity using a balancing ball to demonstrate the Bernoulli principle
Balancing Ball

A ball stably levitated on an invisible stream of air is a dramatic sight. Try to pull the ball out of the air stream—you can feel a force pulling it back in.

Science activity demonstrating balance and the center of gravity
Balancing Stick

The distribution of the mass of an object determines the position of its center of gravity, its angular momentum, and your ability to balance it.

Science activity to simulate natural selection among predators and prey
Bean-Counter Evolution

In this simulation game, teams of predators equipped with genetically different “mouths” hunt for “prey.” Over time, the fittest among the predators and prey dominate the population, modeling the process of natural selection.

Science activity to create a toy that sounds like a swarm of buzzing bees
Bee Hummer

When you spin it around, this toy sounds like a swarm of buzzing bees.

Science activity that demonstrates a color illusion
Benham's Disk

Rotate this black-and-white pattern at the right speed, and the pattern appears to contain colored rings. You see color because different color receptors in your eyes respond at different rates.

Science activity demonstrating the Bernoulli principle
Bernoulli Levitator

The Bernoulli principle explains how atomizers work and why windows are sometimes sucked out of their frames as two trains rush past each other. Choose from two versions of this Snack—small or large.

Science activity demonstrating angular momentum
Bicycle Wheel Gyro

A spinning bicycle wheel resists efforts to tilt it and point the axle in a new direction. Any rapidly spinning wheel exhibits this gyroscopic property—you can use this tendency to take yourself for a spin.

Science activity demonstrating color afterimage phenomenon
Bird in a Cage

You see color when receptor cells in your eye’s retina are stimulated by light. If one of these adapts to a stimulus because of long exposure, it responds less strongly—changing the colors you see!

Science activity demonstrating the blind spot phenomenon
Blind Spot

The eye’s retina receives and reacts to incoming light and sends signals to the brain, allowing you to see. One part of the retina, however, doesn't give you visual information—this is your eye’s “blind spot.”

Science activity demonstrating the phenomenon of light scattering
Blue Sky

When sunlight travels through the atmosphere, blue light scatters more than other colors, leaving a yellowish hue to the transmitted light. The scattered light makes the sky blue; the transmitted light makes the sunset red.

Science activity demonstrating light polarization and stress patterns
Bone Stress

When certain plastics are placed between two pieces of polarizing material, their stress patterns become dramatically visible in a brightly colored display. A stressed plastic object can be used to illustrate stresses found in bones.

Science activity that experiments with rocket designs and a PVC launcher
Bottle Blast Off

Experiment with rocket designs and a PVC launcher to discover how high—and how far—you can make your rockets go.

Science activity to build a rubber-band-powered rolling plastic water bottle
Bottle Racer

In this modern adaptation of a classic toy—the spool racer—a plastic water bottle is propelled by energy stored in a wound-up rubber band.

Science activity to make water boil at room temperature
Boyle-ing Water

The temperature at which water boils depends on pressure. You can demonstrate this by dramatically lowering the pressure in a water-filled plastic syringe at room temperature.

Science activity demonstrating transcription and translation
Breakfast Proteins

Model the central dogma of molecular biology by constructing a colorful chain using a simple code (and some delicious cereal).

Science activity that demonstrates how some light sources flash on and off many times a second
Bronx-Cheer Bulb

Some light sources may appear to wiggle and flash when you give them the raspberry, but the only thing wiggling is you.

Science activity demonstrating buoyancy and semipermeability in soap bubbles
Bubble Suspension

This beautiful investigation illustrates the principles of buoyancy and semipermeability.

Science activity demonstrating the physics of bubbles
Bubble Tray

Bubbles are fascinating. What gives them their shape? What makes them break or last? What causes the colors and patterns in the soap film, and why do they change?

Science activity investigating spectroscopy
CD Spectroscope

Turn an old CD into a spectroscope to analyze light—you may be surprised by what you see.

Science activity to convert your cell phone into a Miniscope
Cell Phone Miniscope

Open your eyes to the amazing world of the ultra-tiny when you convert your cell phone into a portable, picture-taking Miniscope using a simple plastic lens from a laser pointer.

Science activity that explores the properties of soap films and relates them to the properties of plasma membranes
Cellular Soap Opera

Use soap film to model a cell membrane.

Science activity that demonstrates center of gravity
Center of Gravity

Here’s an easy way to find the center of gravity of a long, thin object, even if the object’s weight is unevenly distributed.

Science activity that demonstrates electrostatic charge
Charge and Carry

Tired of electrostatic experiments that just won’t work? This experiment will produce a spark that you can feel, see, and hear.

Science activity demonstrating visual perception illusion
Cheshire Cat

Under most circumstances, both of your eyes receive fairly similar views of the world around you. You fuse these views into a single three-dimensional picture. But what happens when your eyes receive different images?

Science activity that demonstrates a magnetic field created by electromagnet
Circles of Magnetism

Create a magnetic field that is stronger than Earth's field by using electric currents, and a compass needle will orient itself parallel to the new field.

Science activity that demonstrates the dominant eye phenomena
Circles or Ovals?

You have two eyes, yet you see only one image of your environment. If your eyes receive conflicting information, what does your brain do?

Science activity that explores series and parallel circuits
Circuit Workbench

Build a simple circuit board and easily connect small holiday lights in a variety of ways to learn some of the characteristics of series and parallel circuits.

Science activity to build a musical instrument that uses vibrations
Coffee-Can Cuíca

Build a homemade cuíca (“kwee-ka”)—a musical instrument that originated in Africa but is commonly played during Carnival festivities in Brazil.

Science activity that demonstrates temperature perception
Cold Metal

Your hand isn't always a good thermometer. When you touch a variety of materials, some will seem warmer or colder than others, even when they're at the same temperature.

Science activity that demonstrates color perception illusion
Color Contrast

In this investigation, you'll discover how colors seem to change when you place them against different-colored backgrounds. You need to consider this phenomenon when you pick out colors for carpeting or walls or when you're painting a picture.

Science activity to explore variations in skin color and tone
Color Me Human

Skin—we’ve all got it, and it comes in a range of colors and shades. Find a few partners and explore the question of nature vs. nurture by comparing the skin on different parts of your body.

Science activity that demonstrates effect of color filters on perception
Color Table

A brightly colored picture takes on a whole new look when you view it through a colored filter, which transmits some colors and absorbs others. Using a colored filter, you can even decode secret messages.

Science activity that demonstrates perception of additive color mixtures
Colored Shadows

Learn about human color perception by using colored lights to make additive color mixtures.

Science activity that demonstrates fluid pressure and buoyancy
Condiment Diver

Changes in fluid pressure affect the buoyancy of a Cartesian diver made from a condiment packet. The diver floats, sinks, or hovers in response to pressure changes.

Science activity that demonstrates conductivity of solutions
Conductivity Meter

This simple and portable device lets you test the conductivity of liquids anywhere, any time.

Science activity that demonstrates convection
Convection Currents

Here's a simple and visually appealing way to show convection currents in water. Warmer water rising through cooler water bends light, allowing you to project its motion onto a screen.

Science activity that demontrates the movement of a fluid undergoing convection
Convection Detection

A bag of colored water inside a CD case shows the mesmerizing movement of a fluid undergoing convection.

Science activity that demonstrates the effect of air density on sound
Conversation Piece

Sound energy spreads out as it travels away from a source, but a balloon filled with carbon dioxide gas can focus sound, acting like a lens to create a loud spot.

Science activity that demonstrates effect of temperature on density
Cool Hot Rod

Changes in temperature cause objects to expand or contract. Try this experiment and directly observe the expansion and contraction of a metal tube.

Science activity demonstrating paths of light reflection
Corner Reflector

Two hinged mirrors create a kaleidoscope that shows multiple images of an object. When you set the hinged mirrors on top of a third mirror, you create a reflector that always sends light back in the direction from which it came.

Science activity that demonstrates resonance in a pendulum
Coupled Resonant Pendulums

Two pendulums suspended from a common support will swing back and forth in intriguing patterns if the support allows the motion of one pendulum to influence the motion of the other.

Science activity that demonstrates resonance in pendulums
Coupled Resonant Pendulums 2

By taking advantage of resonance, you can cause two pendulums to swing in identical cycles.

Science activity that demonstrates the critical angle phenomenon
Critical Angle

A transparent material, such as glass or water, can actually reflect light better than any mirror. All you have to do is look at it from the proper angle.

Science activity to discover how a variety of traits in a group of living specimens can impact evolution
Critter Comparison

Take an inventory of a variety of traits in a group of living specimens, and discover that even small inherited differences have the potential to impact a population’s long-term survival and evolution.

Science activity that uses a coil of wire, a paper cup and a magnet to create a radio speaker
Cup Speaker

Wind up a coil of wire, attach it to the bottom of a paper cup, hold a magnet nearby, and listen to the radio! You’ve made your own speaker.

Science activity that demonstrates the Curie point phenomenon
Curie Point

A piece of iron ordinarily will be attracted to a magnet, but when you heat the iron to a high enough temperature (called the Curie point), it loses its ability to be magnetized. Heat energy scrambles the iron atoms so they can’t line up and create a magnetic field—this Snack is a simple demonstration of this effect.

Science activity to demonstrate the Magnus effect by launching cups with rubber bands
Curveball Demonstrator

Throw ‘em a curve—and demonstrate the Magnus effect—by launching cups with rubber bands.

Science activity to demonstrate pi using circumference and string
Cutting Pi

String and scissors are all you need to find pi all around you.

Cylindrical Mirror

A flat mirror will always reflect an image that's right side up and reversed right to left. A cylindrical mirror can produce images that are flipped upside down and images that are not reversed. The image you see in a cylindrical mirror depends on the orientation of the mirror and the distance between you and the mirror.

Science activity to explore underwater color perception
Deep Blue

Use photographs and colored light bulbs to see how changing light conditions affect the apparent color of deep-sea organisms.

Science activity that demonstrates adaptation in visual perception
Depth Spinner

When you watch a continuously rotating spiral, the motion detectors in your eyes become adapted to that motion. Then, when you look away, the world seems to move toward or away from you.

Science activity that demonstrates how differently shaped ears affect your hearing
Designer Ears

See how differently shaped ears affect your hearing.

Diablillo cartesiano de condimento

Los cambios de presión que ejercen los líquidos afectan la flotabilidad de un diablillo cartesiano hecho con un paquete de condimentos. El diablillo flota, se hunde o se desplaza en respuesta a los cambios de presión.

Science activity that demonstrates diffraction using a candle or flashlight bulb and two pencils
Diffraction

You can easily demonstrate diffraction using a candle or a small bright flashlight bulb and a slit made with two pencils. This bending is called diffraction.

Science activity that demonstrates a heat engine
Dipping Bird

A dipping bird is an example of a heat engine. It converts a difference in temperature between its head (cooled by evaporation) and its bottom (at room temperature) into cyclical motion.

Science activity that demonstrates perception of camouflage and movement
Disappearing Act

Some animals blend in with their surroundings so well that they’re nearly impossible to see until they move. Compare what you see when a camouflaged figure remains still to when the figure is moving.

Science activity that demonstrates the index of refraction
Disappearing Glass Rods

Glass objects are visible because they reflect some of the light that shines on them and bend or refract the light that shines through them. If you eliminate reflection from and refraction by a glass object, you can make that object disappear.

Science activity that demonstrates neuroplasticity
Distortion Goggles

Distort your vision with special goggles and see what your brain learns.

Science activity that uses falling dominoes to model signal transmission in a neuron
Domino Effect

Your nervous system transmits information as electrical impulses that move through the long bodies of nerve cells. In this Snack, falling dominoes simulate many aspects of the process.

Science activity that demonstrates the Doppler effect
Doppler Effect

When a sound source moves in relation to you, its pitch changes. From this, you can determine whether the source is moving toward or away from you, and you can estimate how fast it’s going.

Science activity that demonstrates linear and rotational kinetic energy
Downhill Race

Two objects with the same shape and the same mass may behave differently when they roll down a hill. A cylinder with a heavy hub accelerates more quickly than a cylinder with a heavy rim.

Science activity that uses a pendulum and a marker to create beautiful designs
Drawing Board

A marking pen remains stationary and a platform swings beneath the pen, acting as a pendulum. As the platform swings, the pen marks a sheet of paper that is fastened to the platform, generating beautiful, repetitive patterns.

Drip Chamber

Make a captivating moving artwork by illuminating a thick, clear liquid with a cell phone flashlight.

Science activity that demonstrates reflections in a kaleidoscope
Duck Into Kaleidoscope

With this mirrored kaleidoscope, you can create hundreds of images of whatever you place inside. The basic structure is a triangle, but mirror tiles can be formed into other shapes and angles as well.

Science activity that demonstrates the art of natural dyes
Dye Like a Natural

Stain your clothes on purpose, bringing the colors of nature to your own wardrobe: use colorful molecules found in natural organisms and objects to dye fabrics or other textiles.

Science activity to investigate earlobes
Ear Sort

Survey a wide variety of earlobes and decide for yourself if sorting their shapes into two groups—“free” or “attached”— is as simple as it sounds.

Science activity that explores the relative sizes of the earth and moon and the distances between them
Earth and Moon

Use different-sized spheres to explore the relative sizes of the earth and moon and the distances between them.

Science activity that demonstrates the eddy current phenomenon
Eddy Currents

When a magnet is dropped down a metallic tube, the changing magnetic field created by the falling magnet pushes electrons around in circular, eddy-like currents. These eddy currents have their own magnetic field that opposes the fall of the magnet. The magnet falls dramatically slower than it does in ordinary free fall inside a nonmetallic tube.

Science activity that models the motion of electrons
Electric Current Model

Model the motion of electrons through a wire by pushing on a circle of small magnets around the rim of a large magnet.

Science activity that demonstrates corrosion, using saltwater and electricity to etch patterns on metal
Electrical Etching

The chlorine in saltwater can corrode many metals, including stainless steel, leaving them pitted and rough. Speed along the process with electricity, and rapidly etch a pattern onto stainless steel.

Science activity demonstrating static electricity
Electrical Fleas

Static electricity makes the sparks when you comb your hair on a cold day, and it makes balloons stick to the wall at a birthday party. Here, static electricity makes electric “fleas” jump up and down.

Science activity to change the measured weight of an object without touching it
Electromagnetic Antigravity

A current-carrying wire changes the weight of mounted magnets resting on an electronic scale—simple but dramatic proof of the Lorentz force, the phenomenon at work in most electric motors.

Science activity detecting electric charge
Electroscope

By suspending pieces of tape from a straw, you can build an electroscope—a device that detects electrical charge.

Everyone Is You and Me

Looking for Everyone Is You and Me? Your Father's Nose is an alternate Snack that relates to the same general principles.

Science activity measuring density of a liquid
Eyedropper Hydrometer

Construct a simple hydrometer that you can use to compare the densities of different solutions.

Science activity demonstrating a visual illusion
Fading Dot

A fuzzy-colored dot that has no distinct edges seems to disappear. As you stare at the dot, its color appears to blend with the colors surrounding it.

Falling Feather

Prove to yourself that Galileo was right—in a vacuum, two different weights will fall at the same acceleration.

Science activity that demonstrates calculating the acceleration of gravity using simple materials
Falling for Gravity

Calculate the acceleration of gravity using simple materials, a cell phone, and a computer to record, watch, and analyze the motion of a dropped object.

Science activity creating music with gravity
Falling Rhythm

Space weights along a string so they make a regular rhythm of beats when they strike the ground.

Science activity that demonstrates action-reaction pairs described in Newton’s Third Law
Fan Cart

Build a low-friction cart and explore Newton’s third law.

Science activity that demonstrates an ambiguous figure optical illusion
Far-Out Corners

At first glance you might see a bunch of boxes here, but, in fact, there are no boxes at all. A closer look reveals you're looking at a cluster of corners lit from below.

Science activity demonstrating how changes in atmospheric pressure feel
Feeling Pressured

Feel changes in atmospheric pressure by stepping into an extra large garbage bag—a breathtaking experience.

Science activity that infuses vegetables with a tasty brine—instantly—using a syringe
Flash Pickling

Infuse vegetables with a tasty brine—instantly—using a syringe.

Science activity to observe shapes floating inside your own eye
Floaters

Gazing at a blue sky, you may see shapes drifting through your field of view—blobs and squiggles called floaters. Why do they jump away when you try to get a better look?

Science activity that demonstrates levitation with electrostatics
Flying Tinsel

By experimenting with positive and negative charges, you can suspend tinsel in the air. (No need to reveal it's just electrostatic repulsion.)

Science activity that demonstrates how clouds form
Fog Chamber

In the atmosphere, clouds usually form when moist air cools as it rises to higher altitudes. You can create the same effect by rapidly expanding the air in a jar.

Science activity that explores the carbon cycle
Follow the Carbon

Model the carbon cycle and its principal reservoirs and flow rates using rice.

Science activity that explores fractal patterns and how they’re formed
Fractal Patterns

Lightning bolts, river deltas, tree branches, and coastlines are all examples of patterns in nature called fractals. In this Snack you get a striking hands-on introduction to fractal patterns and how they are formed.

Science activity that demonstrates the kinetic behavior of gas
Gas Model

A fun way to visualize gas molecules constantly in motion, pinging and ponging against each other and the walls of whatever container they're in.

Science activity that explores the properties of gases and the anatomy of an egg
Gassy Eggs

Discover properties of gases and learn about the anatomy of an egg by observing different boiled eggs.

Science activity that demonstrates gel electrophoresis
Gel Electrophoresis

Simulate the process of manipulating DNA by using electricity to separate colored dyes.

Science activity that demonstrates how geysers work
Geyser

Natural geysers form when underground chambers fill with water and are heated geothermally. When the water is heated to its boiling point, the geyser erupts, spewing its contents—and the cycle starts again.

Science activity that demonstrates an image formed by a lens
Giant Lens

A large hanging lens creates upside-down images of distant objects and right-side-up images of nearby objects. You can locate the upside-down images by using a piece of white paper as a screen. The right-side-up images are harder to find.

Giant Sieve Sorter

Create a series of boundaries that keep some things out while letting other things through.

Science activity that explores heat absorption by different-colored materials
Give and Take

Use temperature-sensitive liquid crystal to monitor temperature changes and show that dark-colored materials absorb and re-emit the energy contained in light more readily than light-colored materials.

Science activity that demonstrates luminescence and flourescence
Glow Up

Different kinds of light can be used to study life.

Science activity that demonstrates light scattering in the atmosphere
Glue-Stick Sunset

Model the scattering of light by the atmosphere—which makes our sky appear blue and our sunsets red—by shining a flashlight through clear hot-glue sticks.

Science activity that demonstrates lateral inhibition in perception of boundaries
Gray Step

Two slightly different shades of the same color may look different when there’s a sharp boundary between them. But if the boundary is obscured, the two shades may be indistinguishable.

Science and engineering activity to make a record player
Groovy Sounds

In this classic activity, make a record player out of simple materials and listen to your favorite vinyl LP—no outlet required.

Science activity that demonstrates charge in a battery
Hand Battery

When you place your hands on metal plates, you and the plates form a battery.

Science activity that shows the effect of temperature on pressure
Hand-Held Heat Engine

Can you get the liquid in a so-called "hand boiler" to travel up and then back down again without turning it over?

Science activity that demonstrates use of nonstandard measurements and simple ratios for estimating sizes or distances
Handy Measuring Tool

Many of the numbers we use in science have never been measured directly; we only know them from indirect measurements. How far is it to the sun? What is the diameter of Saturn’s rings? You can use nonstandard measurements and simple ratios for estimating sizes or distances.

Science activity that uses electricity to break water into its elemental components
Having a Gas with Water

Build a simple electrolysis device using a 9-volt battery wrapped in oil-based modeling clay, trap the two gases produced, and end with a bang as you test their composition.

Science activity to play music by wrapping a string around your head
Head Harp

Wrap a string around your head and pluck it to play music.

Build an inclinometer, a tool that can measure the height of a distant object, no matter how far away it is
Height Sight

Build an inclinometer, a tool that can measure the height of a distant object, no matter how far away it is.

Science activity that demonstrates static electricity
Holding Charge

Use static electricity to stick a straw to the palm of your hand, a window, a door, a wall—or just about anywhere.

Science activity that demonstrates an optical illusion
Hole in Your Hand

You have two eyes, yet you see only one image of your environment. If your eyes receive conflicting information, what does your brain do?

Science activity that explores infrared radiation through a parabolic mirror
Hot Spot

Though you can’t see infrared radiation light with your eyes, you can focus it with a mirror or a lens and feel the warmth it produces. Try this Snack and you'll also learn how parabolic shapes concentrate energy.

Science activity that explores growth rates for cultured cells
How Many HeLa?

Dividing cells expand exponentially.

Science activity that examines fluid pressure, force, mechanical work, and biomechanics
Hydraulic Arm

When you push the plunger on a syringe, water is forced into a second syringe, extending its plunger and lifting a mechanical arm. The process illustrates aspects of fluid pressure, force, mechanical work, and biomechanics.

Science activity to explore hydraulics with a pair of dueling syringes
Hydraulic Battle

Two different-sized syringes full of water are connected together. Push on one and feel the force—multiplied—in the other.

A science activity that demonstrates a straight rod passing through a curved slot
Hyperbolic Slot

If you see a straight rod and a curved slot, common sense says the rod can't possibly fit through the slot. But if the rod is angled and rotated through space and the slot is the exact right shape, it will pass through.

Science activity experimenting with a frozen water balloon
Ice Balloons

Have a ball experimenting with a frozen water balloon—and learn about water chemistry, phase changes, and density.

Science activity demonstrating electrolysis of water
Indicating Electrolysis

Break up water into hydrogen and oxygen gas with a simple electrolysis device, and use an acid-base indicator and a magnet to create groovy swirls of color.

Science activity to investigate infrared electromagnetic radiation
Infrared Remote

Investigate infrared electromagnetic radiation by using your television remote control as a source and a digital camera as a detector.

Science activity that explores the relationship between light, area, and distance
Inverse-Square Law

We all know that the farther away we get, the dimmer a light will look. The question of how much dimmer it looks was answered a long time ago. Here’s an easy way to repeat that discovery.

Science activity to investigate convection
Inverted Bottles

Investigate convection by using food coloring and water at different temperatures.

Science and art activity on visual perception
Jacques Cousteau in Seashells

Seeing is a cooperative effort involving your eyes and your brain. Your eyes may perceive a group of dots, but it’s your brain that has to decide whether or not the dots form a pattern that means something.

Science activity that demonstrates differences in density
Klutz-Proof Density Column

This density column always returns to its original three layers—no matter how many times you shake it up.

Science activity that uses gelatin to demonstrate behavior of filters and lenses
Laser Jello

Gelatin can be used for much more than a sweet treat. It can also act as a smoked lens—which allows you to view total internal reflection—or as a color filter.

Science activity to investigate patterns in laser light
Laser Speckle

A laser pointer and a frosted light bulb are all you need to investigate laser speckle, grainy patterns in laser light that seem to move differently depending on your visual acuity.

Science activity that demonstrates lateral inhibition in visual perception
Lateral Inhibition

Do receptors in our eyes act independently, or do they influence each other? Look through some simple paper tubes and explore how your eyes work.

Science activity that uses a spectroscope to explore white light through leaf material
Leaf Filter

Photosynthesis requires light, but plants don’t use all the colors that make up white light. Use a spectroscope to explore the absorption and transmission of white light through leaf material.

Science activity that explores the size and scale of microscopic biology
Life Size

Explore the size and scale of microscopic biology.

Science activity that explores the behavior of common night-lights controlled by photocell sensors
Light Conversation

Explore the behavior of a common night-light controlled by a photocell sensor, and the interaction of two or more night-lights with one another.

Science activity that demonstrates a simple wind generator
Light Wind

Use wind to power a motor and generate enough electricity to light an LED.

Science activity that investigates reflections
Look into Infinity

If you've ever been between two mirrors that face each other, such as in a barbershop or a beauty salon, you're be familiar with the seemingly endless line of images fading into the distance. This Snack recreates this effect.

Science activity investigating visual perception
Looking a Little Spotty

By digitally manipulating an image, you can test how well your brain can see something where—at first glance—there appears to be nothing but spots.

Science activity that investigates the perception of projected moving images
Magic Wand

When you view a projected slide show or a movie, where is the picture? Is it on the film, in the air, on the screen, or in the eye of the viewer? This Snack will help you investigate and locate this type of image.

Science activity using levitating magnets to model Earth’s atmosphere
Magnetic Atmosphere Model

Ring magnets stacked on a pencil model Earth’s atmosphere, demonstrating how both density and pressure decrease with height.

Science activity to model how the arrangement of domains in a magnet affects its overall strength
Magnetic Chains

Build a model using a scale and tiny spherical magnets to show how the arrangement of domains in a magnet affects its overall strength.

Science activity that demonstrates diamagnetism
Magnetic Fruit

When we think about objects that respond to magnets, fruit usually doesn't come to mind. Watch a rare-earth magnet repel a grape and discover different kinds of magnetism.

A science activity that makes the patterns of a magnetic field visible
Magnetic Lines of Force

Iron filings will line up parallel to a magnetic field, making the pattern of the field visible. This is a simple Snack to build—and because the filings are trapped in a bottle, they don’t make a mess.

Science activity that shows how electricity and magnetism interact
Magnetic Pendulums

The current generated when one copper coil swings through a magnetic field will start a second coil swinging, showing some of the ways that electricity and magnetism interact.

Science activity that explores magnetic lines of force
Magnetic Shielding

Magnetic-field lines pass through cardboard, air, and certain other materials, depending on whether they're permeable or nonpermeable. Test different materials to see which are which.

Science activity that explores an electromagnet
Magnetic Suction

Have you ever wondered how an old-style doorbell works? This Snack shows you how. A coil of wire with current flowing through it forms an electromagnet that acts very much like a bar magnet. The coil will magnetize an iron nail and attract it in a remarkably vigorous way.

Science activity to make an instrument that creates the sound of rain falling
Make Your Own Rainstick

The rainstick is a traditional instrument thought to have originated in Chile, where cactus spines are inserted into dried, hollowed-out cactus branches that are then filled with pebbles, raw rice, or dried beans.

Science activity that demonstrates force and acceleration of marshmallows
Marshmallow Puff Tube

Experiment with cardboard tubes of different lengths to see how far you can blow a marshmallow.

Science activity that demonstrates visual perception of faces
Michelle O (formerly Vanna)

Your brain gets used to seeing familiar things in certain ways. When the brain receives a strange view of a familiar object, the consequences can be intriguing.

Science activity that demonstrates finding the approximate masses of very small things
Microbalance

Make a balance that weighs very light things.

Science activity that will allow you measure things that are too small to measure with commonly available means
Micrometer Caliper

Make a device sensitive enough to measure the thickness of a sheet of paper or the diameter of a human hair.

Science activity that demonstrates lactose digestion by lactase
Milk Makes Me Sick

Use glucose test strips to investigate the function of the lactase enzyme and discover what it means for milk to be "lactose free."

Science activity demonstrating that magnets can affect things that aren’t magnetic
Mind the Magnetic Gap

A swinging aluminum plate stops dead in the presence of a strong magnetic field, demonstrating the presence of eddy currents.

Science activity that demonstrates how mirrors work
Mirror Reversal

Mirrors seem to reverse left and right, but not up and down. Actually, they don’t do either.

Science activity that investigates perception of reflections
Mirrorly a Window

When your brain expects to see one thing and is presented with something quite different, you may feel some peculiar sensations.

Modelo de desintegración radiactiva

Arroja cien monedas. Retira todas las que queden en “cruz” y arma una columna con ellas; repite… De esta manera, tú has generado tu propio modelo práctico para representar el fenómeno de la desintegración radiactiva.

Science activity that demonstrates magnetic field coupling
Modulated Coil

Transfer the sound from an iPhone, iPod, or radio to the speaker of a cassette-tape player by merely holding a coil of wire near the player when it's running—without a cassette in place.

Science activity that explores audio signal transmission
Modulated LED

An LED connected in place of a headphone will flicker at the same frequencies that the headphone would have vibrated. If the light hits a solar panel connected to a speaker, it can reconstruct the sound.

Science activity that demonstrates light wave interference
Moiré Patterns

Moiré patterns appear whenever one semitransparent object with a repetitive pattern is placed over another. They can be used to demonstrate wave interference.

Science activity that demonstrates angular momentum
Momentum Machine

You’ve probably seen an ice skater spinning on the tip of one skate suddenly start to spin dramatically faster. This speeded-up rotation results from a sudden redistribution of mass. You can make yourself suddenly spin faster while sitting in a rotating chair.

Science activity that demonstrates electromagnetism
Motor Effect

This simple device shows that when an electrical current flows through a magnetic field, a force is exerted on the current. This force can be used to make an electric motor.

Science activity that uses de-shelled eggs to explore diffusion and osmosis in cells
Naked Egg

Use de-shelled chicken eggs as models for investigating diffusion and osmosis across plasma membranes.

Science activity that investigates geometry of non-round rollers
Non-Round Rollers

The most common closed and curved plane figure that has a constant width as it rotates is the circle. Surprisingly, however, there are other figures that have this property. You can construct a variety of these shapes with a compass and straightedge. The rollers you can build with this Snack behave in seemingly paradoxical ways.

Oboe de pajilla

Al cortar dos “labios” en el extremo aplanado de una pajilla de refresco y soplar con la presión adecuada, puedes hacer que los sonidos resuenen en la pajilla.

Science activity that models ocean acidification
Ocean Acidification in a Cup

Create a carbon dioxide–rich atmosphere in a cup and watch how it diffuses into the water beneath it, causing the water to become more acidic. Ocean acidification is a change that can be harmful to marine life.

Science activity that demonstrates the brightness of two light sources
Oil Spot Photometer

When an oil spot on a card is illuminated equally from both sides, it mysteriously disappears. This allows you to compare the brightness of the light sources on either side of the card.

Science activity that demonstrates wave interference
On the Fringe (formerly Bridge Light)

When light hits two slightly separated transparent surfaces, part of the light will be reflected from each surface. If the distance between the surfaces is a multiple of half the wavelength of any one color of light, destructive and constructive interference will occur, producing an interference pattern.

Orejas de diseñador

Investiga cómo orejas de diferentes formas afectan tu audición.

Science activity that demonstrates resonance of sound waves
Organ Pipe

You can amplify a tuning fork by holding it over a pipe and changing the length of the pipe. At certain pipe lengths, the pitch made by the tuning fork sounds very loud as it resonates with the air column in the pipe.

Science activity that uses data to explore natural cycles and unnatural changes in our atmosphere
Our Changing Atmosphere

Graph carbon dioxide data from the National Oceanic and Atmospheric Administration (NOAA) to learn about natural cycles and unnatural changes in our atmosphere.

Science activity that explores the relationship between volume, density, and pressure
Out of Sink

Change a bottle’s shape to affect the buoyancy of a Cartesian diver inside of it. Make the diver rise when the bottle is squeezed in just the right way.

Person with shadow.
Outdoor Shadows

Go outside and trace an outline of your shadow. Wait a while, try again, and watch how your shadow changes over time.

Science activity that demonstrates a solar cell transforming light into electricity
Output of a Solar Cell

Measure the efficiency of solar cells as they convert sunlight to power.

Science activity that demonstrates energy transformations
Over the Hill

Explore energy transformations by rolling a marble on a track.

Science activity that demonstrates a visual illusion
Overlapping Spots

You have two eyes, yet you see only one image of your environment. How does your brain interpret brightness when each eye perceives it separately?

Pájaro en una jaula

Tú ves color cuando las células fotorreceptoras en la retina de tu ojo son estimuladas por la luz. Si dichas células se adaptan a un estímulo prolongado, responden con menos sensibilidad ¡y los colores cambian!

Science activity to play songs by banging the end of a PVC pipe against your palm
Palm Pipes

Banging the open end of a PVC pipe against the palm of your hand makes a musical sound. The tone depends on the length of the pipe. Simple songs can be easily played.

Science activity that demonstrates an image produced by a parabolic mirror
Parabolas

What you perceive as an object in this Snack is really an image in space, created by two concave mirrors. This illusion would do credit to any magician.

Science activity to make a parachute out of simple materials
Parachute Plummet

Make a parachute using simple materials and watch how the forces of gravity and air resistance affect it as it falls.

Science activity that models the energy released in an earthquake
Pasta Quake

Break spaghetti to create a “pasta magnitude scale” that models the energy released in an earthquake.

Science activity that demontrates pendulums of different lengths swinging to their own rhythms
Pendulum Snake

Ten pendulums of different lengths swing back and forth at different rates. As they swing, they move in and out of interesting patterns.

Science activity that demonstrates the chemistry of a battery
Penny Battery

Use two different metals and some sour, salty water to create an inexpensive battery.

Science activity that models how elements are organized in the periodic table
Periodic Pasta Table

Create a three-dimensional model of the periodic table that uses sticks of spaghetti to show how trends of atomic properties are used to organize elements into periods and families.

Science activity that investigates peripheral vision
Peripheral Vision

Test the limits of your peripheral vision and measure how much you can see out of the corner of your eye. You’ll find that you can detect motion at a wide angle, colors at a narrow angle, and detailed shapes at a surprisingly narrow angle.

Science activity that demonstrates persistence of vision
Persistence of Vision

When you look through a narrow slit, you can see only a thin strip of the world around you. But if you move the slit around rapidly, your eye and brain combine these thin strips to make a single complete picture.

Science activity that demonstrates how a lenless camera works
Personal Pinhole Theater

Have you ever heard of a camera without a lens? Get an inside look at how a lensless camera works.

Science activity that demonstrates Einstein's photoelectric effect
Photoelectricity

Recreate the experiment that proved Einstein’s theory that light waves are made up of quantized energy—what we now call photons.

Science activity that demonstrates photosynthesis
Photosynthetic Floatation

Show that gas is produced during photosynthesis.

Science activity using straight lines to learn about circles
Pi Graph

Use straight lines to learn about circles.

Science activity to estimate pi with the random tossing of toothpicks
Pi Toss

Randomly toss some toothpicks, with pi as your reward.

Science activity that visualizes convection cells
Pie-Pan Convection

Visualize the fluid motion of convection cells. For this activity, all you need is soapy water, a heat source, and some food coloring—the effect caused by the rising and sinking fluids is spectacular.

Science activity that demonstrates magnification by a pinhole
Pinhole Magnifier

A pinhole in a card can act like a magnifying glass, helping your eye focus on an object that is very close to you. However, by limiting the amount of light that reaches your eye from the object, the pinhole also makes the object appear dimmer.

Science activity that demonstrates resonance of sound waves
Pipes of Pan

Separate the hum of background noise into some of its different frequencies.

Art & Science Activity to explore reflection and light.
Pixel Tube

Rolls of shiny Mylar bundled into a tube together create a dazzling pixelated view of the world.

Science activity that demonstrates human visual perception of images on a smartphone
Pixels, Pictures, and Phones

Learn about screen technology and human visual perception by investigating color images up close. Even the fanciest smartphone screen only has three colors.

Science activity using light projected through a drop of water to reveal an abundance of tiny organisms
Plankton Projector

Who needs a microscope to see what lives in a drop of water? Instead, shine a laser pointer through a drop of water and be dazzled by a display of tiny organisms.

Science activity that experiments with brine shrimp behavior
Plankton Rainbow

Brine shrimp swim in different directions in response to light. But do they respond equally to all colors of light?

Science activity that explores how graphing can reveal patterns in data
Plot the Dot

Graphs can reveal patterns that lead to deeper understanding of phenomena. Collect some data from ordinary objects to reveal a constant in nature.

Science activity that demonstrates a creative exploration of light through a pinhole viewer
Poking Fun at Art

Set up some red, green, and blue lights and build a simple pinhole viewer to investigate colorful and creative mixtures of light.

Science activity that demonstrates light and color mixing through a pinhole viewer
Poking Fun at Color Mixing

Mix red, green, and blue light using a pinhole viewer and conduct simple scientific investigations into human color perception.

Science activity that demonstrates how light travels through a pinhole viewer
Poking Fun at Light Rays

Build a simple pinhole viewer and set up some colored lights to investigate how light gets from Point A to B.

Science activity that demonstrates light and mathematical relationships through a pinhole viewer
Poking Fun at Math

Investigate pinholes with a simple viewing device and some colored lights, and collect data to create real mathematical formulas.

Science activity that demonstrates light polarization
Polarized Sunglasses

When light reflects from nonmetallic surfaces, it becomes polarized—the reflected light is usually vibrating more in one direction than others. Polarizing sunglasses reduce this reflection when the polarizing lenses are oriented properly.

Science activity that demonstrates colors of polarized light
Polarized-Light Mosaic

Using transparent tape and polarizing material, you can make and project beautifully colored patterns reminiscent of abstract or geometric stained-glass windows.

Science activity that demonstrates how volume, pressure and temperature are related.
Pop Bottle

Twisting a plastic water bottle changes its volume, pressure, and temperature—and ends with a bang.

Science acitivity that explores decomposition with worms
Productive Poop

Given the right conditions, worms can accelerate the breakdown of rotting food and produce rich compost in return.

Science activity that demonstrates proprioception
Proprioception

Even with our eyes closed, we have a sense of our body parts and their position thanks to proprioceptors in our muscles, tendons, joints and inner ear. They (and our brains) provide a sense of body orientation and movement.

Pulgas eléctricas

La electricidad estática produce chispas cuando te peinas en un día de frío y hace que los globos se peguen a la pared. Aquí, la electricidad estática hace que las “pulgas” eléctricas comiencen a saltar.

Science activity that investigates the pupil
Pupil

You can watch the pupil of your eye change size in response to changes in lighting. You can also experiment to determine how light shining in one eye affects the size of the pupil in your other eye.

Science activity that models radioactive decay
Radioactive-Decay Model

Throw one hundred coins, remove all those that come up tails, and place them in a pile, repeat—you'll have made yourself a hands-on model for radioactive decay. The piles graphically show the meaning of the term “half-life.”

Science activity that transmits sounds through your body instead of the air
Radiohead

Most of the time, we hear sounds transmitted through the air, but that’s not the only way to hear things.

Science activity that explores environmental data
Raining On Your Data Parade

Sometimes when you’re looking at data, you come across something surprising—a measurement that’s so unusual, you wonder if it’s correct. Take a look at some actual data from a rain gauge, then investigate what is likely to be accurate, and why.

Science activity to design, build, and test a circulatory system
Re-Engineering the Circulatory System

Engineering isn’t just about physics; it’s part of life sciences too! Using simple materials, students can design, build, and test their own model circulatory system, and then figure out how to make it better.

Real Image

Looking for Real Image? Parabolas is an alternative Snack that relates to the same general principles.

Science activity that demonstrates electrostatics
Remote-Control Roller

Rub a balloon on your head, then watch a soda can race across the floor. As you observe the interplay between electrons and protons, you’ll also discover why clothes cling together in a dryer.

Science activity that demonstrates resonance in a pendulum
Resonant Pendulum

By exerting very small forces at just the right times, you can make a massive pendulum swing back and forth in very large swings.

Science activity that demonstrates resonant frequencies
Resonant Rings

This device graphically demonstrates that objects of different sizes and stiffness tend to vibrate at different frequencies.

Science activity that demonstrates resonant frequencies
Resonator

Explore resonance to discover how objects vibrate at certain frequencies. When you shake your Resonator at just the right frequency to cause one dowel to vibrate violently, another dowel may hardly vibrate at all.

Science activity that explores visual perception
Reverse Masks

One mask protrudes from the black surface like an ordinary face, and the other is indented into the surface. When you close one eye and view the two masks, they both look like they are protruding, and when you move sideways, the indented mask seems to turn to follow your movement!

Rodillo a control remoto

Frota un globo en tu cabeza, luego observa cómo una lata de refresco corre por el piso o una mesa. Al observar la interacción entre los electrones y los protones, también descubrirás por qué la ropa se pega en una secadora.

Science activity that demonstrates light polarization
Rotating Light

White light is made up of all the colors in the rainbow. When polarized white light passes through a sugar solution, each color’s direction of polarization is changed by a different amount. The colors change as the depth of the solution changes or as the polarizing filter is rotated.

Science activity to make a simple battery that will light an LED
Saltwater Pentacell

Make a battery by creating five simple cells from aluminum foil, copper wire, and saltwater, and connecting them in series. Use the battery to light an LED.

Science activity that investigates deodorant's effects on skin bacteria
Salty Pits

Explore how different deodorants work and what that means for the bacteria in your armpit.

Science activity that explores the twinkling of stars by beaming a laser pointer over a hot plate
Scintillating Little Star

Why do stars twinkle? Have a scintillating experience by making your own “light twinkler.” Use a hot plate and laser to show that light can change direction and appear to twinkle.

Science activity that produces musical sounds only you can hear
Secret Bells

Create your own personal sound system with a coat hanger and a string, producing musical sounds that only you can hear.

Science activity that explores  DNA sequences, or the genetic code
Secret Codon

Write a message in DNA.

Science activity to explore a developing plant embryo
See Inside a Seed

Soaked in water, dried beans spring to life. Learn your way around a legume as you explore the various structures that protect and feed a developing plant embryo.

Science activity to observe the process of plant development
Seed Germinator

What goes on underground when seeds are sprouting? Make yourself a window onto the process of plant development.

Science activity that investigates the structure of the retina
Seeing Your Retina

A dim point of light will cast a shadow of the retina's network of blood vessels onto the retina itself. Try this activity and you'll be able see the blood supply of your retina—and your blind spot.

Science activity that models the patterns of sunlight and shadow on Earth
Self-Centered Globe

Place an Earth globe in sunlight, and you can align it so the patterns of light and shadow match those on real Earth

Science activity that explores the relationship between filament and flashlight bulb
Sensitive Filament

The exposed filament from a 100-watt incandescent light bulb is wired in series with a flashlight bulb and a 9-volt battery. Blow on the filament and the flashlight bulb gets brighter.

Science activity that uses color chromatography to discover the secret colors hidden in black ink
Separation Anxiety

Color chromatography uses capillary action and the fact that different types of ink migrate different rates. Use this technique to discover the secret colors hidden in black ink.

Science activity that models ground failure in a phenomenon called liquefaction
Shaky Sediments

This Snack models ground failure in a phenomenon called liquefaction. See what happens when you shake up structures, loose sediments, and water in a simulated earthquake.

Science activity that demonstrates the effects of ocean acidification
Shell Shifts

Increasing amounts of carbon dioxide in the atmosphere are making the ocean water more acidic. See why this makes it harder for shellfish to build and maintain their shells.

Science activity that demonstrates a short circuit
Short Circuit

Current flowing through a wire heats the wire. The length of a wire affects its resistance, which determines how much current flows in the wire and how hot the wire gets.

Science activity demonstrating one of your visual system’s many idiosyncrasies
Shrinking Spot

In this perception illusion, an automatic reflex causes light entering one eye to change what you see in the other eye, demonstrating one of your visual system’s many idiosyncrasies.

Science activity that simulates subsurface magmatism and surface volcanism
Single-Serving Volcanism

Simulate subsurface magmatism and surface volcanism by injecting a sweet sauce into a single-serving cup of gelatin.

Science activity that explores sound waves
Siren Disk

Sounds can be made in some surprising ways. Blowing air through a spinning disk full of holes can make a variety of pitches.

Science activity that demonstrates depth perception
Size and Distance

By removing clues to the actual size and distance of an object, you can trick your brain into thinking that two similar objects of different sizes are really the same size.

Science activity to demonstrate the size of microscopic objects
Sizing Up

Discover some big surprises in the microscopic world.

Science activity that explores the relationship between the temperature and volume of a given amount of gas
Sizing Up Temperature

Discover the relationship between temperature and volume of a given amount of gas.

Science activity exploring the body's defense against pathogens
Skin Shield

Explore the body’s first line of defense against pathogens.

Science activity that investigates skin surface area
Skin Size

Work out the approximate surface area of your skin while also figuring out the approximate amount of atmospheric force pushing on it.

Science activity that uses off-center rotation to produce interesting vibrational behavior
Skippy

Skippy is a mechanical creature that uses an off-center rotation, or eccentric motion, to produce interesting vibrational behavior.

Science activity that explores an optical illusion
Sliding Gray Step

Make one shade of gray look like two by putting it against two different color backgrounds.

Science activity that investigates waves
Slinky in Hand

With just a Slinky and your hands, model transverse wave resonances as well as longitudinal wave resonances. Learn about nodes and antinodes of motion and compression.

Science activity that investigates motion through position, speed, and acceleration
Slow Your Roll

In this activity, you can investigate the motion of a slow-moving wheel on a track by using a timer, tape, and permanent marker.

Science activity that models light wave interference
Soap Film Interference Model

By experimenting with this model of light-wave addition, you can understand the behavior of light reflecting off soap films. Why do you see blue or red? It’s all a matter of phases.

Science activity that demonstrates light interference in soap
Soap Film on a Can

Why do we see colors in oily water and soap bubbles? Experiment with soap film to observe the behavior and colorful appearance of different wavelengths of light.

Science activity that uses gravity to turn soap film into an ever-shifting array of colors
Soap Film Painting

Under the influence of gravity, a thin soap film constantly changes thickness, creating an ever-shifting array of colors.

Science activity investigating surface area and light
Soap-Bubble Shapes

Make three-dimensional geometric frames of different shapes, then dip them in a soap solution to form fascinating and colorful soap films.

Science activity to to explore how curved mirrors reflect images
Soda Can Mirror

Wrap a piece of Mylar around a soda can to make a cylindrical mirror. Then create your own anamorphic art to explore how curved mirrors reflect images.

Sonidos maravillosos

Haz un tocadiscos con materiales simples y escucha tu LP de vinilo favorito. No se requiere una fuente de electricidad.

Science activity that demonstrates sound conduction
Sound Bite

When you listen to a radio or music player, you normally hear the sound coming from the speaker or headphones. But in this Snack, you pick up sound vibrations through your teeth!

Science activity that encourages participants to ask questions and carry out investigations
Sound Cups

This Snack encourages participants to ask questions, carry out investigations, and use their senses to find a person whose Sound Cup matches theirs, and then together recreate the sounds they hear.

Science and art activity that demonstrates pitch and vibration
Sound Sandwich

By making simple adjustments to this noisemaker, you can raise or lower its pitch and make different kinds of sounds.

Science Activity that explores how accelerometers work.
Spaghetti Accelerometer

How does your phone know to rotate its screen when you rotate the phone? Make a model of your phone’s accelerometers, tiny sensors in your phone that detect changes in motion. 

Science activity that explores frequencies, forced vibrations, and resonance
Spaghetti Resonance

If you shake an object or otherwise make it vibrate at its natural frequency, it will start to vibrate more and more, often violently enough to break.

Science activity that demonstrates properties of convex mirrors
Spherical Reflections

Round mirrored holiday ornaments packed together in a box create an array of spherical reflectors. Study the properties of spherical mirrors while you create a colorful mosaic of reflections.

Science activity that explores unexpected patterns
Spinning Blackboard

When you draw on a spinning disk, you make unexpected patterns. If you try to draw a straight line, for instance, what appears on the disk is a spiral. The patterns you make result from adding the motion of your hand to the spinning motion of the disk.

Science activity that investigates rotation and perception
Spinning Cylinder

A piece of pipe with a mark at each end is set rotating and spinning at the same time. In the blur of the moving cylinder, one of the marks appears three times, forming a stationary triangle.

Science activity demonstrating how a square wheel will roll smoothly on a round surface using catenary curve
Square Wheels

A square wheel will roll smoothly, with its axle at a constant height, on a surface with bumps of the right size and shape.

Science activity exploring geologic formations
Squeeze Box

Compress layers of sediments in an easy-to-build deformation chamber to see folds, faults, and other geologic features develop in real time.

Science activity that demonstrations adaptation in the visual system
Squirming Palm

Stare at a waterfall for some time and then stare at the rocks nearby—the rocks will appear to be moving upward. This illusion is known as the waterfall effect, and you can recreate it—without getting wet.

Science activity that demonstrates sound localization
Stereo Sound

Sound from a given source must travel slightly different distances to reach your two ears, which each hears the sound at a slightly different time. This lets you determine where a sound source is located.

Science activity that demonstrates chaotic motion
Strange Attractor

Patterns of order can be found in apparently disordered systems. This pendulum—a magnet swinging over a small number of fixed magnets—is a very simple system that shows chaotic motion for some starting positions of the pendulum. The search for order in the chaos can be engrossing.

Science activity that demonstrates resonance in a musical instrument
Straw Oboe

By cutting two “lips” into the flattened end of a soda straw and blowing with just the right pressure, you can make sounds resonate in the straw.

Science activity that investigates standing waves, nodes and antinodes.
String Machine

By attaching a string to two small electric motors rotating in the same direction, you can create and play with a special class of waves called standing waves.

Science activity that explores the relationship between magnetic fields, voltage, and electrical circuits
Stripped-Down Generator

In an electric power plant, steam or water power is used to move huge coils of wire past extremely strong magnets, generating megawatts of electricity to light whole towns. This Snack uses your muscles to move ordinary magnets past a small coil of wire, generating milliwatts of electricity—just enough to light an LED. The two generators work at very different scales, but they are both based on the same physics principles.

Science activity investigating electromagnetics and motors
Stripped-Down Motor

A coil of wire becomes an electromagnet when current passes through it. The electromagnet interacts with a permanent magnet, causing the coil to spin. Voilà! You’ve created an electric motor.

Science activity to see how water levels change with temperature.
Swelling Seas

Watch water swell and shrink with heating and cooling. 

Science activity that demonstrates the mathematics of the center of gravity
Take It from the Top

Simple wood blocks can be stacked so that the top block extends completely past the end of the bottom block, seemingly in a dramatic defiance of gravity. The trick is to move the top block first and then proceed on down the stack.

Science activity that demonstrates the primary and secondary colors of light
The Three Little Pigments

Investigate how light and color interact by aligning cyan, magenta, yellow, and black transparencies.

Science activity that demonstrates depth perception
Thread the Needle

Close one eye and you eliminate one of the clues your brain uses to judge depth. Trying to perform a simple task with one eye closed demonstrates how much you rely on your depth perception.

Science activity that explores how water temperature and salinity are tied to the tidal cycle
Tidal Ties

Examine water-depth measurements from the Exploratorium and make predictions about water temperature and salinity.

Science activity that explores tidal patterns
Tide-O-Matic

Model the equilibrium theory of the tides and discover why there are two tide cycles per day, why the heights of the tides change over the course of a month, and why the tides occur about an hour later each day.

Science activity to make a mini indoor compost pile
Tiny Hot Pile

No yard? No problem. Make a mini indoor compost pile, and look for evidence of microbial metabolism.

Science activity that demonstrates pressure and weight distribution
Tired Weight

You don't need to be a sideshow strongman to calculate the weight of a car—you can do it by measuring the surface area of each tire's "footprint" and the pressure inside each tire.

Science activity that explores images from a concave mirror.
Touch the Spring

Place an object in front of a concave mirror so it isn't visible to the viewer, but the viewer can see the mirror image of the object formed in space. Try to touch the image—your fingers pass right through it.

Science activity that demonstrates color mixing with printer ink
Truly Primary Pigments

The primary colors of pigment are cyan, magenta, and yellow, which can be mixed to make many other colors, but demonstrating this can be difficult if you want to use markers. Using printer ink to make your own markers will give you more accurate results.

actividad científico que demuestra la relación del olfato con el gusto
Tu sentido del gusto

Percibimos sabores a través del trabajo de distintos tipos de receptores en nuestras lenguas. Estos receptores se unen a las moléculas químicas en nuestros alimentos y transmiten la información sobre dichos químicos a nuestros cerebros.

Tubo lanzador de bombones

Experimenta con tubos de diferentes longitudes para ver cuán lejos puedes hacer viajar un bombón con tu soplido.

Science activity that explores rotational inertia
Twirling Tester

Rotational inertia (sometimes called angular inertia) is the rotational analog to linear inertia. This Snack explores what makes some turning objects harder to start and stop than others

Science activity that demonstrates Thomas Young's two-slit experiment
Two-Slit Experiment

Recreate the two-slit experiment by shining a laser pointer through two narrow slits and observing the interference pattern on a distant screen.

A science activity that demonstrates the two-slit interference phenomenon
Two-Slit Wave Model

By experimenting with this model of light-wave addition, you can understand the behavior of light as it passes through two narrow slits.

Science activity that demonstrates Bernoulli’s principle by blowing between two empty cans
Uncanny Motion

On a flat tabletop, arrange two empty cans so you can blow between them. Depending on one small detail, the cans either come together or move apart.

Science activity that demonstrates components of force and motion
Vector Toy

A mass hangs from a string attached to the front of this walking toy (also called a "ramp walker"). Watch as the string almost draws the vectors that make the toy work.

Science activity to bring vegetable scraps back to life
Vegetable Revival

Use vegetable scraps from your kitchen to investigate the stem cells of plants and their potential for new growth.

Science activity that models the structure of a virus
Viral Packaging

Solve the problem that took viruses millions of years to conquer by efficiently fitting nucleic acid and proteins into a small package.

Science activity visualizing sound waves
Vocal Visualizer

Croon a tune, croak like a frog, hum, hoot, or holler—you don’t need to be Pavarotti to transform laser light into dazzling shapes and patterns with the power of your voice.

Science activity that demonstrates the force of pressure in a vortex
Vortex

Water forms a spiraling, funnel-shaped vortex as it drains from a soda bottle. A simple connector device allows the water to drain into a second bottle.

A science activity exploring the law of conservation of mass
Wait, Weight, Don't Tell Me!

A simple chemistry experiment—adding baking soda to vinegar—seems to challenge the law of conservation of mass.

Science activity that demonstrates the behavior of a spherical lens
Water Sphere Lens

A round bowl of water can act as both a magnifier and a lens.

Science activity demonstrating centripetal force
Water Spinner

When you spin a tank of water on a lazy Susan, the surface of the water forms a curve called a parabola.

Science activity to create an instrument that produces sound from a vibrating stretched membrane
Water-Bottle Membranophone

Kazoos and drums are membranophones—instruments that produce sound from a vibrating stretched membrane. Here, a water bottle and a paper tube make a membranophone that sounds like a saxophone crossed with a clarinet.

Science activity that demonstrates the force of inertia
Whack-a-Stack

A simple stack of wood blocks demonstrates that an object at rest will remain at rest unless a force causes it to move.

Science activity used to determine the field diameter of a compound microscope
What's the Size of What You See?

Determine the field diameter of a compound microscope.

Science activity that reveals the earth’s magnetic field using hanging magnets
Where's North?

Observing the effects of the earth’s magnetic field on magnets is similar to some of the earliest experiments conducted on magnets.

Science activity that demonstrates persistence of vision
Whirling Watcher

A series of slits moving rapidly past your eye allows you to see images in short bursts. Such rapid but fragmented views of moving objects can make the objects appear to jerk along, change speed, or even move backward.

Science activity to visualize air pressure with the help of a self-rolling pet toy
Wiggle Pressure

Self-rolling pet toys can wiggle around, pushing on objects a lot like air molecules do, modeling many of the behaviors of the molecules in gases.

Science activity that demonstrates distances with a composite reflection
Your Father's Nose

In a normal mirror, you see your own face looking back at you. But what if you looked into a mirror and saw a face that was partly yours and partly another person’s?

Science activity that demonstrates smell's effect on taste
Your Sense of Taste

We perceive flavors through the work of different types of receptors on our tongues—those that detect sweet, sour, salty, bitter, and umami (savory). These receptors bind to chemicals in our food and transmit the information about the chemicals to our brains.


Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Attribution: Exploratorium Teacher Institute

  • Education
    • Teacher Institute
    • Tools for Teaching and Learning
      • Science Snacks
        • Browse by Subject
        • Special Collections
        • Science Snacks A-Z
        • NGSS Planning Tools
        • Frequently Asked Questions

Connect with us!

  •   Sign up for our educator newsletter
  •   Follow #ExploEDU
  •   Teacher Institute YouTube
  •   Teacher Institute Facebook
  •  teacherinstitute @exploratorium.edu
Exploratorium
Visit
Join
Give

Pier 15
(Embarcadero at Green Street)
San Francisco, CA 94111
(415) 528-4444

Contact Us

  • Plan Your Visit
  • Buy Tickets
  • Hours
  • Getting Here
  • Calendar
  • Tactile Dome
  • Store
  • About Us
  • Become a Member
  • Donate
  • Event Rentals
  • Jobs
  • Volunteer
  • Press Office

Get at-home activities and learning tools delivered straight to your inbox

The Exploratorium is a 501(c)(3) nonprofit organization. Our tax ID #: 94-1696494
© 2021 Exploratorium | Terms of Service | Privacy Policy | Your California Privacy Rights |