for newbies you can better teach them ARM be it Cortex M, boards available as low as $10 upto whatever you want to spend if you include lcd etc. 68k is a bit obsolete although the principles stay the same.
I was asked to teach a *classic architecture*, and 68k is the best choice. ARM will be considered for the Master Degree class, which is focused on advanced embedded programming, for which I have some working experience but no qualification as a teacher because I am not a teacher.
My task is 20 hours in total, and it's available to be chosen but it's not an obligatory laboratory that a student needs to pass in order to pass an examination, while the ARM-programming-class is something like more than 40 hours and it's an obligatory laboratory.
So, the *cool* factor is exactly teaching m68k, otherwise, the campus would have chosen a different candidate for the event