Beth, I agree. Its cool to use engineering to solve old and new problems. Its also important to maintain a creative mindset through imagination foster by fairytales. Also, the problem illustrates that not only men are good engineers but women as well. This problem should be presented to the Myth Busters to validate the math behind the solution.
Fun example and certainly one that could and should be used to encourage interest in STEM among girls. While the math may play out, I like your mom's version that the slippers were magic. Afterall, some fairy tales are better left to just that--fairy tales.
It won't be too much longer and hardware design, as we used to know it, will be remembered alongside the slide rule and the Karnaugh map. You will need to move beyond those familiar bits and bytes into the new world of software centric design.
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