Folk pedagogy encourages what is believed to be best practice, but cannot validate best practice.We have evidence computing teachers do not use evidence. Davide Fossati and I studied 14 CS teachers from three institutions (http://bit.ly/1BV9uNo). Fossati asked them about times they made a change in their teaching practice; why did they make the change, and how did they know if it was successful or not. They used intuition, informal discussion with students, and anecdotes. Not a single teacher used evidence such as class performance on a test or homework.Without evidence, teachers rely on intuition informed by experience. Sometimes that intuition may be informed by years of experience. Sometimes that experience is not at all relevant.