Build a Fizz Inflator - Science Bob Baking Soda and vinegar create an ACID-BASE reaction and the two chemicals work together to create carbon dioxide which starts to fill the bottle, and then moves into the balloon to inflate it.
Ed Dancing raisins activities. Lots of fun experiments. I have done this experiment, and seen the entire class become silent out of curiosity. It is a great engagement piece for a lesson, and it can be hands on if you ask for volunteers!