When you are a teenager you can't work at full time job. And also, you can't work when you study. There is one way that teenagers can get some money. It's part-time jobs on summer holidays. You can distribute flyers, for example. It will take about 3-5 hours a day, but this part-time job can give you a little cash which you can use. As for me, i prefer to be a waiter (waitress если женского пола). It is very interesting to know what food people can order.
Советую улучшить этот вариант некоторыми дополнениями со своей стороны.