I left this comment last time somebody posed this image:

I love to watch Bob Ross as much as the next guy, and he was a wonderful man with a wonderful, gentle, soothing personality, but he didn't really teach his audience anything, not even how to paint. All he did was provide step-by-step instructions equivalent to paint-by-numbers. A good art teacher, the kind you'd want teaching in a high school, for instance, would teach you things like technique, a bit of art history, the different movements i.e. styles, and encourage creativity and personal expression. He really doesn't belong on this list.