To preschoolers, the changing colors of fall leaves may seem like something close to magic. This simple science lesson will help preschoolers to understand the process that leaves go through in the fall when they begin to change colors and what plants need to live and grow.

What You Need

Plants need to eat food to grow just like people do. Plants make a special kind of sugar for food using sunlight and a chemical inside them called chlorophyll that turns them green. We know when plants are getting enough food to eat because they are bright green and look healthy. During the spring and summer when there is lots of sunlight, plants make a lot of food and are a bright green color.

In the fall, there is not as much sunlight and plants can not make as much food. The trees start to get ready to go to sleep for the winter just like bears go into hibernation. During the spring and summer they have made enough food for them to survive through the winter. Because they aren’t making as much food, the leaves on the trees don’t make the bright green color so they start to show all of the other colors that they have inside like, red, oranges, yellow, and brown.

Have preschoolers go outside and pick a variety of fresh leaves from the trees. Explain that you are going to find out what happens to leaves when they can not make enough food. Tell preschoolers that leaves get their food through the tree branches and when you pick them they don’t have any way to get food.

Spread the picked leaves out on a cookie sheet and set them in your science center. Make a handout for each preschooler that has a simple leave template duplicated 5 times. Have preschoolers look at the leaves and find a crayon that matches the color that the leaves are when they are first picked. Have preschoolers color the first leaf template to match the leaves.

Leave the leaves out for an entire week and each day have preschoolers visit the science center and look for any changes in the leaves. Have preschoolers color one leaf on their handout each day to match the color of the leaves.

At the end of the week, have preschoolers look at the leaves. The leaves may be wrinkled and dry. The leaves may have changed colors and look brown instead of green. Ask the preschoolers why they think the leaves look different than they did when they were on the tree. Tell the preschoolers that the leaves could not make any food so they started to change colors. The leaves weren’t getting any water so they started to dry up.