Come Together Kids: Mini Marshmallow Shooters (or Pom Pom Poppers) put a balloon over the top half of a stiff plastic cup, with the bottom of the cup removed. Pull of the balloon tie with the pompom inside, and POP!
Are you looking for a fun game to play that will keep the kids busy? These Balloon Cup Shooters are awesome! And they will definitely keep the kiddos entertained for a few hours. All you need are plastic cups, balloons, duct tape and ping pong balls.
The Ketchup Experiment! Kid friendly site with lots of neat experiments! It has one that makes a rocket out of a film canister, which would be good for an grade space unit, but it has to many kid friendly expiriments. Great site for any science teacher.
A marshmallow (or other thing) popper from Real Simple. Cut off the bottom of the cup, cut off the top of a balloon, put them together, and then sling pop things around. Add some pretty duct tape around the cup to hold the balloon on better.
Fun & Frugal Gift Idea: Homemade Marshmallow Shooter Kit