This activity is easiest to do with at least two people. One person can make the soap film and hold the handle while the other person explores how the film behaves.
Shape the bubble frame into a rectangle. Holding the frame by the handle, immerse the entire frame into the bubble solution.
Lift the frame up by the handle until the bottom of the frame is slightly out of the bubble solution and the straws are parallel to the tabletop. You should have a rectangular soap film between the two straws. If there isn’t any soap there try immersing and lifting the frame again.
Hold the soap film in front of the black construction paper or other black material. Carefully observe the surface of the film. Blow gently on the film and watch what happens.
Repeat the first two steps if the bubble pops while you are completing the steps below.
Wet your finger in the bubble solution. Gently poke through the soap film with your finger. What happens? Can you move your finger around in the film? Now wet a non-soapy finger in plain water and poke it into the film. What happens?
Try gently poking a dry finger through the soap film. What happens now?
Make a new film on the frame. Roll a film can or PVC tube section in the bubble solution to coat its surfaces. Grasp the film can near one end, and remove it from the solution. If films have formed across the openings of the can, pop them. Insert one end of the film can through the soap film on the frame. If the film pops, make another and try again.
When you successfully insert a bubble-coated film can through the soap film, leave the can in this position and have your partner pass an object (such as a pen) through the openings of the can, from one side of the film to the other (see photo below). Can you move the film can around in the soap film?
Try putting a dry film can through the soap film. What do you notice?
Based on your observations, what conditions allow objects to pass through the soap film without popping it? What conditions cause the film to pop? Do you think the flexibility of the film influences its ability to resist popping? Why or why not?