Here's an idea:
Photosynthesis Lesson - Air and Plants (adapted from Project Learning Tree)
Fill a bowl with fresh water.
Mix baking soda into the water to provide carbon dioxide to the plant.
Place an aquatic plant inside a drinking glass.
Lower the glass sideways into the bolw of water until the glass fills with water and no air bubbles are left in the glass. Then turn glass upside down without letting in air. The glass should rest on the bottom of the bowl. Aim light from a lamp toward the plant on the side of the glass.
You will see small bubbles forming on the leaves in the water. Most bubbles will come from the side of the plant nearest the light. After about an hour, you will see that a large bubble will form on the top of the water inside the glass. This bubble contains the oxyen that the plant has made.
If you are outside, just put a plastic bag over a large leaf on a plant or a tree. It will take only a few minutes to start sweating.
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Evelyn Margolin
Sacramento, CA
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