The student pilot in the low-wing airplane reported that after landing, she exited the runway on to a taxiway which was occupied by the high-wing airplane which had landed before her. She attempted to pass the high-wing airplane on its left, but her right wing struck the other airplane's left wing lift strut. Her airplane then continued to the right, turning about 180° with her right wing striking the propeller of the high-wing airplane, followed by her propeller striking the right wing of the high-wing airplane. The flight instructor in the high-wing airplane reported that after exiting the runway on to a taxiway he "felt a small hit on the left side." He saw a low-wing airplane make a right 180° turn around the front of his airplane and impact the right wing of his airplane. The low-wing airplane sustained substantial damage to the right wing. The high-wing airplane sustained substantial damage to the right wing. The student pilot reported that there were no mechanical malfunctions or failures with the airplane that would have precluded normal operation.