Grow a Balloon

by Keli Back
(Versailles, KY, USA)

The purpose of my science fair project was to demonstrate how matter can change state. In this case I used a chemical reaction to change a liquid into a gas.

I added 1 cup of vinegar to a small plastic flask. Next, I filled a round balloon with baking soda and stretched the opening around the opening of the flask. When I tipped the balloon up, the baking soda dropped into the vinegar, creating a foamy substance and gas, blowing up the balloon.

I set up the demonstration multiple times for the many people who visited my project at the science fair. Most of the time it was successful, but a few times I ripped the balloon when trying to stretch it around the opening of the flask. Regardless, my demonstration was always a hit with the audience. I would definitely do it again.

Today I am an elementary science teacher and I believe strongly that science fairs are an incredible learning experience for students as young as 3rd grade. People often argue that parents do all the work, but doing research, conducting experiments, and collecting/analyzing data with or without help teaches children how to 'do' science. As they get older, the scientific method and process skills start to make better sense because they have these science fair experiences in their background.

Barry's Response - What's good for the children is good for society. Thank you, Keli, for your detailed description and for being good for the children. I'll bet you still use this demonstration whenever appropriate.

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