Skepticism is one of the cornerstones of scientific learning. Some pseudosciences in domains such as astronomy or pharmacy use a host of issues in everyday life as pretexts for work in the classroom (e.g., astrology) or laboratory (e.g., homeopathy). Chemistry also offers opportunities to promote skeptical thinking in students. Commercial devices such as water magnetizers have been wrapped in a pseudoscientific halo and are widely advertised on radio and television, where they reach a large audience. The water magnetizers provide a unique opportunity to help university and secondary students develop appropriate skepticism against extraordinary claims and use testing as the "touchstone" for their confirmation. (Contains 1 table, 1 figure and 2 notes.)