Here's the cause of the problem: there are NO pre-requisites for the CNC classes.
Generally around half of the students have taken a manual machine shop class, or otherwise have any experience with something other than a hand drill. For the others, not only do they need to learn how to operate the machine, but first learn what a lathe does in the first place!
It's a problem we face because if we require the manual machine shop as a prereq, it cuts down on our enrollment. Okay so that might be true, but there's only so much we can fit into a semester even if everyone has taken the manual class. Instead we have people that don't know the difference between a centerdrill and a drill. Or worse can't measure something with a rule to the nearest 1/16". (imagine using a depth mic after that)
It's a sore subject, I'm not in charge of it obviously. It all goes back to the enrollment problem...we have hundreds of jobs available but the students think "manufacturing" is equal to "assembly line".