Did you know that plants crave sunlight so much that they will bend to follow it? Kids love this simple visual phototropism plant science experiment, and it’s one of our favorite simple experiments for kids.
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Our summer gardening experiment led to several questions about plants. I explained that plants get energy from the sun, and designed this simple experiment to teach my kids how important the sun is to plants. It’s the perfect companion to this week’s Virtual Book Club pick, The Tiny Seed.
Simple Experiments for Kids: Plants and sunlight
What You'll Find on This Page
For this phototropism experiment, we put a tomato seedling in front of a window, and observed that it bent its stem to expose its leaves completely to the sun. We marked which side of the pot the leaves were leaning using a marker. You’ll find an example of this on the right edge of the pot in the photo above. Then we rotated the pot so that the plant was facing away. We did this several times, always marking the edge of the pot that the leaves were closest to. The kids were amazed to find that the plant changed directions to get as much sunlight as possible.
While the photos in this post are from when my kids were very small, it’s an experiment we’ve repeated over the years, explaining what is going on in greater complexity as they grow older.
How to Adapt This Simple Experiment for older kids:
- Ask them to predict what, if anything, will happen to the plant after it is moved in front of the window
- Once the plant moves, ask them to explain why.
Plant Science Picture Books to Read
There are also some great picture books you can read to go along with this experiment, for example:
- Roots by Vijaya Khisty Bodach
- Seed to Plant by Kristin Baird Rattini
- How a Seed Grows by Helene J. Jordan
- From Seed to Plant by Gail Gibbons
Do you have a favorite plant science picture book that I should I add to my list?
The experiment definitely made an impression on then-four-year-old Emma. She spent weeks afterwards drawing plants in the sun, like this:
The little animal on the top right is a bumblebee, pollinating the flowers =)
More Plant Themed Learning Activities for Kids
Extend this simple science experiment with more plant themed learning:
- A simple plant biology exploration.
- Grow grass – and enjoy trimming it (in small quantities!).
- Learn why fruits and vegetables get soft when cooked.
- Explore gardening fun for kids.
- Practice counting with this plant themed coding worksheet for preschoolers.
- Develop math skills with a flower patterning activity.
- Make your own hanging painted flower craft.
- Learn letters by spraying an alphabet garden.
- Make a plant journal.