I guess I would have to say it depends. If my child was involved in many after school activities, and/or spending a lot of time on school work, I would not expect her to have a job during the school year. If she was sitting at home every afternoon doing nothing, darn straight she will be getting to work.
Summers are perfect times for kids to work - and I would say 15 is a good time for that to start.
I also think it would depend on how much spending money the kid needed. If she was asking for money all the time, and/or has very expensive taste in clothing, etc., then I think she should get a job.
Denae