On November 11, 2000, about 1515 hours Pacific standard time, a Schweizer SGS 1-36, N3621R, operated by the Lake Elsinore Soaring Club, Lake Elsinore, California, collided with trees approaching the Skylark Field in Lake Elsinore. The glider was substantially damaged, and the student pilot was seriously injured. The flight was performed under 14 CFR Part 91. Visual meteorological conditions prevailed. No flight plan was filed for the student pilot's solo instructional flight, which originated from the airstrip about 1358. According to the student's flight instructor, on September 23, 2000, he had authorized his student to solo the glider in the local area. Regarding the accident flight, after about 1 hour the student planned to return for landing at the airstrip. Approaching the field, the student misread his altimeter and initiated a circle to lose altitude. Midway through the turn the student realized his error, noted that he was low, and headed directly back toward the airstrip. The glider continued to lose lift, and the student did not initiate emergency procedures to make an off-site landing in nearby available fields. The flight instructor further stated that while attempting to stretch the glide, the glider stalled and collided with tree branches. Thereafter, it impacted the ground hard about 1/2 mile from the airstrip. The glider came to rest in the front yard of a trailer park. The student pilot elaborated by reporting that he believed the accident was caused by his error in checking the altimeter and misreading it by 800 to 1,000 feet.