Baking Soda and Vinegar Rockets (9+)
EXPLOSIONS EVERYWHERE MEANS HAPPY KIDS Told the kids we were making rockets and had them design the body first. I didn't give the kids much guidance except asking them to think about making them aerodynamic.
Then I did a demo of how we'd use baking soda and vinegar to create air pressure, which I'd done with the 7-8s and they'd tried to finesse:
- Pour an inch-ish of vinegar in a water bottle
- Pour a bunch of baking soda into a balloon
- Attach balloon to mouth of bottle
- Lift balloon to drop in baking soda
- Watch balloon expand. Observe how cold and heavy the air is in there. Try stuff.
- CO2 is denser than air.
- This is an endothermic reaction, meaning it absorbs heat, but that can be a little confusing.
I did this as a demo with all of the age groups. Of course, everyone realllly wanted to make a version that would explode off the balloon, but noone quite got the mixture down. So with the oldest, this meant we were finally ready to put our rockets into action.
Using this as inspiration, I showed the kids my model rocket, which had vinegar at the bottom and a saran-wrap package of backing soda tucked inside, hanging precariously from the lid. Shake it up and the baking soda gets loose, the pressure builds up...
At this point, it's a tough design challenge for kids this age and we worked hard to get our "release packages" of baking soda ready in a variety of forms.
And then we took it outside to test!
