Prospect Park is lovely, the zoo is also fun and your living room is pretty swell too. But why does the DIY kids’ birthday party always seem to cost at least $500, even with a Costco cake? To help cut down on the cost as well as the endless preparation for what should be a fairly simple event, here are a half-dozen well-priced birthday party venues you may not have heard of, including a roller rink, a bowling alley and an outdoor adventure park. If you live in Brooklyn Heights or thereabouts, these places aren’t exactly centrally located—but all are worth the trip. (more…)