To explain photosynthesis to students, go through how photosynthesis happens, backing up what you say with visual aids and experiments. Use simple language to explain the lessons. The lessons should happen over the course of at least a week.
- Begin with sunlight
Start by describing the importance of sunlight as an energy source. Describe how it provides the energy that plants need to survive.
- Discuss chlorophyll and chloroplasts
Talk about how chloroplasts are a part of plant cells and that they contain chlorophyll. Discuss the importance of chlorophyll in taking in the sunlight.
- Bring up the other important elements for photosynthesis
Make a list for the kids of the other important molecules needed for photosynthesis, such as water and carbon dioxide.
- Talk about the transformation that takes place
First, discuss how humans breathe oxygen and release carbon dioxide. Then discuss how plants do the opposite, taking in carbon dioxide and releasing oxygen. Use a visual aid such as a balloon to help with the discussion, as it helps to demonstrate that air exists even though the students cannot see it. Discuss how plants use the sunlight they take in and how they mix it with water and carbon dioxide. Point out that the plant converts these ingredients into glucose and oxygen and uses the glucose for food. To help kids understand, explain that glucose is a sugar that even humans eat and use for energy.
- Do an experiment to prove the lesson
Have students place one plant in sunlight with extra nutrients, one plant in sunlight without the nutrients, two plants in the classroom light, one with and without nutrients, and the same in a cupboard without any light. To complete the lesson, have students compare the differences between the plants over a week.