All of our kids have worked some temporary part time jobs that did not seem to have many drawbacks and did help them.
Our DD is a very popular babysitter (when she is not busy with social things) and she worked at a fireworks stand this summer.
DS #1 worked for a friend who is a custom cabinet maker.
DS #3 worked for a friend who has a number of rent houses and he cleaned up after renters moved out, yardwork and painting, etc:
All of those situations had a lot of benefits about learning to work, flexible hours and limited paychecks.
But the situation that was bad was DS #2 started working at Burger King a few months after he turned 16. He was gone way too much and he earned too much money for a kid and got used to having lots of pocket money. He is a great young man but if I could change the past, I would not of allowed him to get that kind of job.