The last thing that comes to mind when most people think about high school gym class is a courtyard designed by Danish architects. But when the administrators at the Gammel Hellerup high school realized the size of the student body had outgrown its current athletic facilities, they commissioned BIG to build a gym below grade that would double as a useable courtyard space above ground. Instead of the boxy high ceilings of a typical gym, BIG used a wave-like ceiling that resembles a small hill from the exterior, one that invites after-class hanging out. The space, like most high school gyms, can work for non-athletic functions as well, and with the included solar panels it reduces the school's carbon footprint. [via Dezeen]