A visiting Japanese glider pilot was undergoing conversion to the "Junior" glider. On her first flight she appeared to be aiming too close to the tugs and pie cart on the left of the strip but she successfully corrected and continued for a normal landing. The instructor judged that she understood the problem and briefed her for the next flight which was to be solo. On final approach she again aimed too close to the parked obstructions but this time she failed to take corrective action. During the landing roll the left wing of the glider was substantially damaged when it collided with a parked tug aircraft. The collision swung the glider through 180 degrees. The tug was less severely damaged. Significant Factors The following factors were considered relevant to the development of the accident: 1. The pilot did not position the glider to give adequate obstacle clearance. 2. The glider collided with a parked tug.