The flight instructor was providing primary flight instruction to a student pilot in a tailwheel-equipped airplane. The instructor reported that as the student pilot was departing from a 5,000 foot-long, dry paved runway, the airplane drifted to the right just after becoming airborne. Unable to correct the drift, the airplane continued off the right side of the runway, and over an area of grass-covered terrain. The instructor said that the student pilot then closed the engine throttle and switched the engine magnetos to the off position, and the airplane subsequently landed hard on the right main landing gear wheel. The airplane sustained substantial damage to the fuselage. A postaccident examination of the airplane did not reveal any preaccident mechanical anomalies that would have precluded normal operations.