Try something you would also benefit from. Adventure parks are a great place, as you can usually do the rides for free. Other good places are arcades, video rental stores, skating rinks, mini-golf parks, and movie theaters. Fast food and grocery stores are not fun, so try to get a job you'd enjoy before you resort to that.
Teenagers can babysit, mow lawns, become baristas, work retail, or deliver pizzas. They can be messengers, food servers, do telemarketing, conduct phone surveys, or get paid to wear signs over their shoulders.