One of my favorite classroom celebrations is Halloween. I usually plan a full day of educational fun around the Halloween theme. I don't care how old you are Dry Ice is just plain cool to play with, and it is relatively inexpensive. I help the kids make mini smoke ring launchers. It's pretty simple just a plastic cup with a hole, large baggie, rubber band, WARM water, and a small piece of Dry Ice. Just make sure you are the one to add the Dry Ice. It's totally safe as long as they don't come into contact with the Dry Ice. Then just have the kids gently tap on the end and let the fun begin!
While I've got the Dry Ice out I put on a little science show for the kids. Add warm water and Dry Ice to a few graduated cylinders and you've got yourself a production. Put in some color tabs to change the color of water or just drop in a light stick and wait for the oohs and aahs. If you really want to get them excited just add a smidgen of dish washing soap. I like to pour it on the kids hands. I'm a Steve Spangler wanna be so for the grand finale I bring out the Boo Bubbles. You can purchase the equipment from his website for under $30. It makes gas filled bubbles. Drop a few of these in the kids hands and you've got Classroom Magic!