I am guessing that you are talking about CEIBS, which is kind of far away from the action, but not impossible to get to. The good news is that the Nanpu Bridge provides much better access to Puxi than the Yan'an Tunnel and the school is reasonably close to it. So, you could try to find a place near the school (not very expensive) or along Longyang/Longdong Rd, or on the Puxi side reasonably close to the road that approaches the bridge (I forget its name and the map doesn't show it). Taxis from the school's area into town cost y60-80 IIRC (~y25 to the subway).