The solo student pilot in a tailwheel-equipped airplane reported that he had completed five touch-and-go landings and maneuvers in the local area before returning for a full-stop landing. While on final approach about 50 ft above ground, he reduced throttle to idle and allowed the airspeed to slow, and the left wing dropped abruptly. The left main landing gear touched down on the runway, the airplane veered to the left into grass, and it then nosed over. The left wing lift strut and the rudder sustained substantial damage. The student pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation. The student pilot failed to submit the National Transportation Safety Board Form 6120.1 Pilot/ Operator Aircraft Accident/ Incident Report.