Pi Day Procession starts at 1:59 p.m.
To participate, please gather in the McBean Theater at 1:30 p.m.

Be sure to parade in the Pi Day procession, lead by the Prince of Pi, Larry Shaw! We'll gather in the McBean Theater at 1:30 p.m. to kick it off.

1 p.m.
Ask a Scientist's Pi Day Puzzles
with Wes Carroll

Very clever people in ancient Greece figured out how to calculate the now-famous ratio between a circle's circumference and its diameter.  They called it pi, and in tribute to their discovery, we still call it by the same name.   Test your cleverness with Pi Day aficionado and math whiz Wes Carroll, who will present a tricky puzzle or two (or three) for you to think about and maybe even solve.  Perhaps in thousands of years they'll remember your discoveries too! 

This event is a sneak peek of the Ask a Scientist Pi Day Puzzle Party at the Bizaar Cafe at 7 p.m. this evening.  Ask a Scientist is an informative, entertaining, monthly lecture series, held at a San Francisco cafe. Each event features a speaker on a current scientific topic, a short presentation, and the opportunity to ask all those burning questions that have been keeping you up at night. 

1:30 p.m.
Pi Procession gathers!
Pick up your Pi Day signs here and join the procession up to the mysterious Pi Shrine! Larry Shaw, the Prince of Pi, leads the way.

1:50 p.m.
Pi Procession leaves for Skylight / Pi Shrine
Parade in an infinite stream of Pi numerals, chanting the Pi Day song. Circumambulate around the Pi Shrine. Voila, you're initiated!

2:05 p.m.
Pie Serving!
Have a slice of sweet pie on us----while quantities last.

1 p.m.
Why Pi?
Find out what's so special about this irrational number! Featuring Exploratorium staff Lori Lambertson and Ron Hipschman.

1:45 p.m.
Pi Day in a Virtual World
The Exploratorium has a museum in the virtual world of Second Life, called the 'Splo.

Come to a Pi Day, mixed-reality event, hosted by staff physicist Paul Doherty. We'll bring you images of Pi exhibits from Second Life, and you'll get to play with real-life versions.

3 p.m.
Question: Name three things you'll find at the Webcast Studio, when we investigate the physics of pie tossing!

Answer: Physics, Cream Pies, and the Three Stooges

Come and join us, for you never know when you'll find yourself needing to (successfully) throw a Whipped Cream Pie at someone!

Players: Paul Doherty {The Professor}; & Norm Ten, Hashim Anderson, and Larry Shaw {The Three Stooges}

10 a.m. to 2:30 p.m. (Reaction at 2:15 p.m.)
Pi(e) Chain Reaction

Celebrate Pi day by creating with a Pi-themed chain reaction with us. Help us complete the chain reaction using common materials and Pi day related objects. Each section of the chain reaction will trigger the next, and it will be completed on-site, just in time for the Pi day celebration.  Stop by the Skylight area to participate, or watch the event!

This activity is available for a limited number of visitors, based on a first-come, first-served basis, and recommended for visitors 9 years old and older.

2 p.m.
Championship Pizza Tossing!
With World Champion Tony Gemignani

Nine-time World Pizza Champion Tony Gemignani will perform an acrobatic pizza tossing show. Audience members will be incorporated and learn how to toss pizzas. Afterwards, meet and greet with Tony. He'll be passing out posters and cards to visitors, as well as selling his book, Pizza.

Tony Gemignani is a nine-time World Pizza Champion and two-time Food Network Gold Medalist. In addition to being featured in the Guinness Book of World Records, he is the proud co-owner of Pyzano's Pizzeria in Castro Valley and co-author of Pizza.

1 p.m. - 3 p.m.
Cutting Pi & Pi String Beading
Join our High School Explainers and volunteers for a personal, hands-on Pi experience.

2 p.m. - 3 p.m.
Spin, Splat, & Spray Art
Revisit the Classic 'Spin Art'---Exploratorium style! Come see how drips and drops create circulate splashes of color and take your creation home to remember Pi Day!

Pi is a number, starting with 3.1415926535… ad infinitum. It's the number you get when you divide the circumference of a circle by its diameter, and it can't be expressed as a fraction. It goes on forever.

This year's Pi Day is also Albert Einstein's 129^th birthday. Happy Birthday, Al!