Activity time: 5 minutes
Materials for Activity
- Raw potatoes (one for each team of two or three participants)
- Plastic drinking straws (one for each participant)
Preparation for Activity
- Try this experiment to become familiar with the process.
Description of Activity
Form teams of two or three participants at work tables. Give each team a raw potato. Ask a participant on each team to select a straw and try to stab the potato with it. (The straw should buckle and bend, barely piercing the potato skin.)
Then, encourage another participant on the team to take a straw, hold it so their thumb seals the top hole, and try to stab the other end into the potato.
Participants will probably find it fun to try the experiment a few more times.
Ask participants to reflect with questions such as:
- Why did covering the hole at the top of the straw drive it deeper into the potato? (The air trapped in the straw gives it enough strength to penetrate the potato; as the straw pierces the potato, the air in the straw compresses, strengthening the straw even more.)
- How does this experiment prove the existence of something (air) which cannot be seen?
Including All Participants
Instead of stabbing the potato with a straw, an individual with limited motor coordination may be able to hold the potato still while a teammate stabs it with the straw.