The A,B,Gs of radiation - "kryptonite", smoke detectors, geiger counters, and cloud chambers (you can actually "see" the trails left by radioactive emissions!)
as you watch the cloud chamber, can you see the difference between the alphas and betas? And why does it seem like some are coming from a different direction than the lantern mantle in the middle...???
To build your own cloud chamber, use a tuna/soup can lid, paint it black, cut about an inch off a larger water bottle, glue it to the black lid, glue a strip of black felt inside around the top, saturate the felt with alcohol (we used 70% isopropyl), place a small piece of lantern mantle in the center, cover with a lid (we used a petri dish), set it level on some crushed dry ice in a styrofoam food container, turn out the lights, and use a flashlight to illuminate! They usually run for around 20 minutes or so :-)
