I thought I should share some of the things that surprise or enrage me. Clearly, I'm thinking here of mathematical strategies or resources that reinforce errors, not political, ethical or world issues.
Take, for example, the mathematical misconception that a square is somehow not a rectangle. In many quarters this is a very strongly held idea. An idea, that (by any mathematical definition) is wrong. However, it's easy to see how this error is reinforced... Read more »