That's the ideal. Except that in the status quo, only the good teachers need to get the kids that don't want to DO anything to DO anything, and the practical consequences for failing to motivate the slackers are nil.
Otherwise, there are two basic possibilities depending on the kid's parents. Either the kid is expected to try and DO something (and does), or the parent only expects child care. In the latter case, avoiding willful destruction and interruption is all that is required … tada, babysitting!
The manager analogy doesn't make sense because managers are much more directly accountable for whether the employees achieve anything for the company while clocking in. If managers' mostly subjective assessments were the only tangible output of employee time and other impacts were felt years later and weren't directly ascribable to an individual manager, then maybe the analogy would work.