The kids loved watching bean seeds sprout. We put five beans in a ziploc bag with a folded wet paper towel. The bags were taped to our classroom window (with names written in permanent marker). Of course we also read "Jack and the Beanstalk
First, he blows some bubbles and, as expected, the kids all pop them. Then, he challenges them to NOT pop the bubbles even if one lands on the tip of their nose. Introduce the concept of self control and launch a discussion about stopping to think before you act. Dustin refers to it as a "bullet" in your year that you can refer back to again and again. "Think about that time when we didn't pop the bubbles..."