Hobbies And Interests
Things You'll Need
Instructions
Use diagrams. Depending on the age of the children, the specifics of the chemical reaction at the heart of photosynthesis may be inappropriate. But the equation can easily be reduced to a simple yetl accurate form: Energy from the sun drives the combination of carbon dioxide and water to produce the sugar glucose and oxygen. Glucose might be a difficult product for kids to understand, but in a diagram it might be represented as an energy packet or human snack. Again, dependent on the age level of your audience, you may be able to illustrate, too, the uses of glucose to underscore its importance: contributing to the formation of starch, a carbohydrate used for energy storage, and to the creation of cell walls.
Incorporate living plants into your lesson. Bacteria and some other organisms also undergo photosynthesis to produce energy-rich sugar, but plants will be the most recognizable and useful example for youths. You can place a houseplant by the window and highlight how its leaves act as solar receptors to the sunlight streaming in. Or you can take a walk in a park, garden or natural area and emphasize how the myriad species of grasses, forbs, shrubs, trees and other vegetation are all interacting with sunlight and conducting photosynthesis. This can help the learning child link the theoretical formulations of the photosynthesis equation with the greenery they are so familiar with.
Highlight the green hue of plants by explaining that it comes from a pigment called chlorophyll -- the technicalities of light-wave reflection that produce the color for the human eye are probably better left for another lesson -- which traps sunlight for use in photosynthesis. Children will hopefully eventually learn more of the specifics of light-capturing pigments, but early on it is valuable simply for them to associate a maple leaf's greenness with photosynthesis.
Emphasize the importance of photosynthesis by simplifying the ecological food web for the kids. A diagram of intermixed food chains would be helpful here. Explain that plants are one of the most important "machines" on the planet for converting power from the sun into energy usable by animals, including people. Point out that the food energy created by plants and other photosynthetic organisms is eventually our food, as well, and that one of the process's byproducts, oxygen, is also of essential importance to all living creatures.