Home » Education » Simple Experiments for Kids: Plants and sunlight

Simple Experiments for Kids: Plants and sunlight

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.

plants and sunlight science experiment

Some links on this site are affiliate links and I may earn a small commission at no cost to you. Thank you! Learn more.

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

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:

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:

Simple Experiments for Kids: Plants and sunlight #edchat #STEAMed #scienceexperiments

More Gardening Ideas for Families

Gardening activities for families to enjoy together.

What are your favorite simple experiments for kids? Do you have another plant themed learning activity to share? Share your recommendations on my Facebook page, or tag me on Instagram

MaryAnne at Mama Smiles
 | Website

MaryAnne is a craft loving educator, musician, photographer, and writer who lives in Silicon Valley with her husband Mike and their four children.

23 thoughts on “Simple Experiments for Kids: Plants and sunlight”

  1. You know, we’ve never done many botany experiments, or not that the kids remember. I should try this with the kids this summer.

  2. Love The Tiny Seed, and the variations of suggestions for how to have fun with this little theme. It’s fantastic to watch the enthusiasm and curiosity build. Adding in some age-appropriate responsibilities is a great addition.

  3. I’m doing thus with my preschoolers. One set of 8 in the class closet, one set of 8 outdoors. We planted sunflower seeds. 5 days later, 6 of the seeds in the closet sprouted. The entire set outdoors did not show any signs of “poking” through the soil. By the end of the week, the set in the closet was standing 4-6″ strong. One seed from the outdoor set had just poked through. What are your thoughts? I’m shocked.

    1. Is the closet warmer? It’s definitely more climate controlled, which might help sprouting. The plants only need light to thrive once they have leaves, so as time hours by your outdoor plants will probably do better, would be my guess. Does that make sense?

  4. heather • wordplayhouse®

    I love how you marked the pot. A wonderful science project to share with children. I just shared on Pinterest!

  5. I just wanted to tell you that I really enjoy your blog. I came upon it sometime last year and I keep returning to see what’s new. You children are adorable by the way. I love your crafts, they are unique.
    .-= Tiyana´s last blog ..Homeschool – Unschool =-.

  6. jeannine: waddlee-ah-chaa

    I love the combination of science and journaling! Emma’s picture and learning makes me smile! Kids love plants, don’t they?! We’ve been planting too. :)
    .-= jeannine: waddlee-ah-chaa´s last blog ..Container Gardening with Children- Square Foot Gardening Style =-.

  7. I thought it was a rake at first :) This is a great experiment, and I always enjoy seeing Emma’s drawings.
    .-= Natalie´s last blog ..Geography Track – Landmarks =-.

  8. Thanks everybody! And Natalie, I can see why you thought it was a rake – I was a little surprised when she said they were flowers ;)

  9. Elisa | blissfulE

    Marking on the edge of the pot is genius! :) I’ll have to try this.
    .-= Elisa | blissfulE´s last blog ..torso back carry =-.

  10. Valerie @ Frugal Family Fun Blog

    Love her drawing! Sounds like she is really understanding the concept quite well. We just read Leaves, Leaves, Leaves and Emily really enjoyed it.
    .-= Valerie @ Frugal Family Fun Blog´s last blog ..Super-Easy Cool Comets =-.

  11. Again, Emma is so intelligent and talented/creative as well.

    This is a fun learning experiment and I like the way you went about doing it with them.
    .-= Susana´s last blog ..A Boy and His Trucks =-.

  12. That’s such a fun learning opportunity. We did something similar when my daughters brought home potted sun flowers from school. They kept asking why the flowers were “bending to the window,” which led to a discussion about why the sun is important for plants.
    .-= Quadmama´s last blog ..Our Mini-Vacation =-.

  13. This is such a great idea. It’s one of the things that has always fascinated me personally about plants (that they can actually move, and quickly!), but I’ve never thought to point it out to my kids. I can think of so many ways to illustrate this now. Thanks for sharing.
    .-= Jaimie´s last blog ..Self Portrait Saturday 8- July 17th- 2010- Almost Two Years Ago =-.

Comments are closed.

Scroll to Top