Learning about trees? Complete your photosysthesis science experiment with this simple science demonstration on how trees breathe.
It’s the perfect addition to your spring STEM activities!
Related: Science Experiments for Kids
HOW TREES BREATHE
THE SCIENCE OF PHOTOSYNTHESIS
What Plants Produce the Most Oxygen?
This science experiment was authored and run entirely by my fourth grader.
Supplies
- Small containers of similar size (we used mason jars)
- Several types of leaves (we used leaves from three trees and two bushes)
- Timer
Conducting the Experiment
We modified the classic science experiment where you sink a leaf in water to watch how it produces oxygen. When a leaf is submerged, you can see the oxygen it produces in the form of bubbles clinging to the leaves.
Monkey hypothesized that the more bubbles a leaf produced, the more oxygen it could make. We gathered oak leaves, maple leaves, holly leaves, and two mystery leaves- one from a tree and one from a bush.
We placed the leaves in equal amounts of water (about a cup per leaf). We let the leaves sit in the water for one hour.
After an hour, we observed which leaves had the most bubbles. The maple leaf had the biggest bubbles, but the reddish mystery leaves from the bush had the most bubbles. The holly leaves and the mystery tree leaves had almost no bubbles.
Through this experiment, Monkey determined that planting maple trees and the red-leafed bush would produce the most oxygen in any environment. 
