I don't have a specific idea on what works and what doesn't with computers, but I do have an enlightening story. I was taking a class at the local community college (with a bunch of college kids half my age). One of the students remarked that calculus cannot be taught without a graphing calculator. That piqued my interest because "back when I was in college", graphing calculators didn't even exist. I asked the kid for details about why a graphing calculator is so essential, and he asked how one could find the graph for an equation. I responded that you calculate first and second derivatives, intercepts, maxima ,minima, and inflection points, and from that you can usually come up with a good idea of what the graph looks like. The kid responded by saying that he always learned it the opposite way: you start with the graph and from that you can deduce information about the maxima,minima, inflection points and intercepts etc. It never occurred to him that you could do it in the reverse manner. Bear in mind that this wasn't a dumb kid, but the material was presented differently because of the availability of the graphing calculator. In the end ,you sort of have the same knowledge, but you aquire the knowledge in a different way. I don't really have an opinion on whether this is good, bad, or neither, but I thought I'd share it anyway since it sort of relates to the OP question.

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