The cloud chamber is one of the oldest detectors for elementary particles. A simple type of a cloud chamber can be built with materials that are easy to purchase. This instruction shows how to build a cloud chamber and gives information on the traces left by particles as well as the particles themselves.
Please download the instruction here: http://www.teilchenwelt.de/material/materialien-fuer-lehrkraefte/selbstbau-einer-nebelkammer/