A few weeks ago, the kids discovered what happens when baking soda and vinegar are mixed together. First, we used pipettes to put drops of vinegar in a dish of baking soda. That made little bubbles! Then we dumped cups of vinegar into cups of baking soda. That made LOTS of bubbles that reminded the students of volcanos!
We learned that the bubbles are carbon dioxide. (The same bubbles in our parents' pop.)
We also had a short lesson on solids (baking soda), liquids (vinegar), and gases (carbon dioxide).
They had a blast and could have spent all day "being scientists!"