Explosions

What does a Chemistry teacher do to entertain a group of visiting French exchange students?  Blow things up, of course! (Isn't that what chemists do?)

Method:
1. Take one empty plastic bottle from a carbonated drink
2.  Spoon in some granules of dry ice (frozen carbon dioxide).
3.. Add a generous amount of cold water
(3a   Hide behind the cloud that forms.)
4. Put the cap on the bottle
5. Toss the bottle away and stand clear
6. Watch the bottle expand as the dry ice sublimes and the gas pressure builds up
7. Enjoy the loud explosion as the bottle bursts.