Many of our science fair ideas are geared toward the student prone to procrastination. If you look through our site, you’ll find many projects that look spectacular but can be whipped up in a single evening. This one doesn’t come under that category, since it requires several days of being set aside. But still, it establishes some meaningful science and has the added advantage of including something bursting into flame.

To show that plants put out oxygen, the experiment collects some of the gas emitted by a plant. After enough has been collected, the student can establish that it’s pure oxygen by placing a small smoldering piece of wood or paper into it, where it will burst into flame.

This idea appeared in Popular Science 80 years ago this month, March 1939.