Many college students have incorrect ideas about the phase changes of water, the three-dimensional and dynamic atmosphere, and other topics which hinder their understanding in the growing A.M.S. On-Line Weather Studies course. Some of these ideas came from children's textbooks and curriculum materials, and some from terms like “vaporizer” and “humidifier,” when they could see the steam or mist coming out. Before college-level science can be grasped, some foundation concepts need to be clear, and errors corrected.