Having adult guidance is very important. Just telling teens to "get a job" isn't.
Making $3000 over a few months at an after school job as a teen isn't a good use of a young person's time in most cases and if they can afford to do other things such as study, learning a language, learning a skill it's a better use of time.
I don't think the kids I've taught who worked needed all those hours to get how budgets and taxes work.