Math topics that need to be put out of their misery. Part 3: Radian measure
So far I’ve written about two topics I feel contribute little to math education. They don’t inspire students to want to learn more about math. They are not topics that are ‘useful’ in real life or as a prerequisite to other ‘useful’ math. Though I plan to do about ten parts to this series, you should know that I could easily write forty parts. I’d say that at least half of the math that we force kids to learn are, to put it mildly, ‘counterproductive.’
But there are other topics that would make my very short list of things that I think are very important and should never be cut from the curriculum. Much of the time saved by eliminating the stale topics could be transferred to expanding the focus on these more essential topics. One such topic is the famous mathematical number π. I teach an elective called math research which is taken mainly by 9th graders, and we spend a few weeks studying different ingenious ways that mathematicians across the globe and across the centuries have devised for approximating this mysterious number.
Ask most adults what Ï€ is and they are likely to say either “I forgot” or “3.14″. Then if you ask them, “But what is Ï€?” and they are unlikely to know. Put most simply, Ï€ is the number of diameters of a circle, any circle, would be needed to wrap around that circle.
Three is too few, but four is too many. It seems to be a little more than three, but how much more? 1/4, 1/5, 1/8? Well it turns out to be quite close, but not perfectly, 1/7, getting the
