Shall we do some fun things with air and water? Everybody likes to make bubbles, and it is interesting to see the many different ways we can make them.

Here's a way we can put some fun into washing dishes. Turn a glass full of air upside down, and push it down to the bottom of a pan or dish (or sink) containing 3 to 4 inches of water. You will see that the air in the glass takes up space and keeps water from entering the glass.

Now slowly tip the glass and observe the air bubbles escaping from it. Put the top of the glass back on the bottom of the pan. You will see that water has somehow entered the glass. If you're doing this while washing dishes, now is the time to finish washing the glass!

These are some other things we can do with air and water:

a. Push a piece of dry, crumpled paper toweling into a dry glass. Be sure that the toweling will not fall out. Invert the glass, and push it to the bottom of the water in the pan. The toweling will remain dry because the air keeps the water out of the glass.

b. Float a small cork in the pan and invert the glass over it. Note the level of the floating cork and explain why its level changed.

If a glass or jar without a bottom can be obtained, it can be set over another floating cork placed next to the first glass. The levels of the two adjacent corks can be compared.

Why do you think the levels of the corks are different?

This next one is REALLY fun!

c. Hold two inverted glasses, one filled with water, one with air, underwater in an aquarium filled with water. Pour air back and forth between the glasses by tipping one glass to the side and trapping the rising air bubbles with the other glass.