i would encourage her, if she was really keen, into jobs that have daytime hours. When paying teens is so cheap, i would worry she would get midnight - dawn shifts at fast food places, and also, think of yourself, because i assume you would have to go pick her up at knock off time - so you might have to drag the whole family off in the car, to go pick her up at 3am for example. (i have no idea of the ages of your other kids etc).

Having a job, CAN teach immature kids to grow up a bit, but still needs some backup - which i'm sure you would give her.

Does she know how to use a lawnmower? (ask locally, if anyone in your neighbourhood needs their lawns done).
Babysitting after school for working parents in your neighbourhood (only a few hours)
What is she good at - could she work as a swim tutor in the holidays or any other sport she is good at (to teach the beginners etc).

having a bank account, paying own expenses, saving up for a car/major goal, meeting the needs of the employer, all good things for her to learn, but maybe in moderation at this age, and maturity level. Who knows, she may cope fine, surprise you and be ready for a more full on part time job this time next year.

you sound like you care about her so much, that's wonderful. My parents gave me zero guidance when i first started earning, apart from demanding i pay board immed, so i blew all the money (minus the board) as i had no clue how to be a smart consumer, how to save, about goals, etc etc.