Buffalo Exchange is a great place to go if you need to clean out your closets and get a bit of cash too. They pay top dollar for used clothing in good condition, and they have a pretty good selection of items to choose from.
When you bring clothes to them, you can choose cash or store credit. Usually, you make out better getting the store credit.
They have some trendy items, and remember that fashion always repeats itself. I'm sure that you can find tons of 80's stuff making it's way back into teenagers' wardrobes.
Break out those parachute pants!