Suction is a misnomer. Air can only push; it can't pull. Knowing this, try to explain how a suction cup works; what holds it to a surface? Playing with suction cups is a great entry to understanding air pressure and how it can change if the volume of a given amount of air changes.
If you can purchase the larger ones, made for installing windows, kids can put them together and try to pull them apart. They can't--even with a few kids on each side they won't be able to pull them apart no matter how hard they try. It's a lesson that clearly demonstrates the power of air pressure.
Use this to learn and reinforce answers to questions such as:
❑ How does suction work if air can't pull?
❑ What holds a suction cup to a surface?
❑ What surfaces will/won't a suction cup work on?
Once students work through the activity, they can capture their observations using the included Lab Notes or probing questions included in the instructions.
Concepts Addressed
♦ It's the weight of air (or water) above you that causes pressure
♦ Air (gas) cannot pull, it can only push
♦ Air's pressure pushes it into every conceivable space
Answer Keys and Teacher Notes address most questions and issues that might arise in this study—you shouldn’t have to do any outside research unless you want to.
Materials Needed Nonconsummables: Various sizes of suction cups. Copies of directions can be placed into page protectors or laminated.
Prep Time Collect materials
Teaching Time About 20 mins depending on accompanying writing assignment.
Student Sheets Scaffolded writing prompts & lab reporting
