And please don't be misled by the phoney ads and pictures of shoppers dancing through the malls with huge shopping bags of goodies. The average shop will pay you $10-$15 and reimburse you a buck or two for your purchases. There are a number with much higher amounts you are to purchase and return--evaluating both the purchase AND the return. Usually a clothing reimbursement is about enough to purchase a pair of socks on sale.
However, with your age you are eligible for or will soon be eligible for a number of different age compliance shops that may involve whether you are carded or not to purchase alcohol, cigarettes or video games. But this stuff is work,not just a lark.