The problem is that you are forcing people who don't care about it to learn it. Ofc they'll take shortcuts.
> Plug and chug is their true desire.
I mean, most tests are very plug and chug so it's no surprise.
Also note that it might be unreasonable to expect students who never used these tools to use them for the right purpose. Mathematica is a complex tool but I can't imagine that much class time is dedicated to the tool itself.