When radioactive elements decay they emit high-speed particles. These can be detected by use of a cloud chamber. The cloud chamber was invented by Charles Thomson Rees Wilson in 1911. The chamber works by saturating the air inside with alcohol vapor. Cooling the chamber with dry ice supersaturates the air. The energetic particles produced by the radioactive decay ionize
The Solar Oven Science activity was developed as a way to target conservation of energy. Some students understand that he sun can be used for heating and cooking but they mistakenly think that this can only work in deserts. Because of conservation of energy solar cooking and heating can work in temperate and even arctic environments. The linked