You just hit the nail on the head ... shops are reluctant to train. Where do you think machinists come from, anyways? Or carpenters or electricians? Kids coming out of public schools sure aren't (on average) 'much to look at'.
Give 'em some training (sort those screws, take the burr off these parts, measure these pins) and insist that they also attend whatever classes are available locally just to keep their jobs. In their 'free-time' at work, let other employees assign them tasks / teach them how to use tools - select steel - run the saw - weld saw blades - use the hoist - measure accurately - and so on. I learned screw profiles from 'the boss', how to remove burrs and pressurize the Karto sprayer from a 'permanent bench hand', make CNC edits by watching the boss and then sneaking them in when he wasn't around. ;-) (makes you a VERY careful operator!)
Chatting with the DeVlieg 43K72 operator alerted me to spindle drop and rebuilding that stinky-butt machine from a basket of parts woke me up to a WHOLE LOT of alignment issues -- straighness of ways, adjusting gibs and so on and on.
Plan to reimburse them somehow ... either in wages (one raise for an "A", another for a "B" nothing for a "C" and extremely shaky ground for anything less than a "C".[gpa for the semester]) or similar pro-rated tuition / books money if you plan on retaining them after training, though.
Best shop I ever worked at for this paid for the tuition upfront (from a pre-approved list of trade-related classes) ... reimbursed for books on a sliding scale and pegged wages to the final GPA for the school year.