Visit the Humus section of the Treeture web site to see how to start your own classroom composting bin. Make a recipe using some of the shade loving vegetables and fruits that you discover. Incorporate math skills with a graphing exercise. Trees help keep the air and soil near gardens moist by releasing water through their stomata in a process called transpiration. This is especially helpful in dry climates.
Flowers help trees too, especially in cities.
When their leaves and petals look droopy, they probably need a drink and so does the tree. Transpiration can be easily demonstrated by placing a clear plastic bag over the leaf attached to a plant and placing the plant in the sunlight for a couple of days. Plastic 2 liter soda bottles can be reused to create mini terrariums in which the transpiration process and the water cycle can be observed. An adult can cut the bottles in half about mid way down the bottle. Plants can be planted in the lower half and then watered.