On February 21, 2000, about 1700 central standard time, a Cessna 150H, N22017, piloted by a student pilot, sustained substantial damage when it exited the prepared surface on takeoff from runway 20 (5,500 feet by 100 feet, dry asphalt) at Alexander Field, Wisconsin Rapids, Wisconsin. The 14 CFR Part 91 flight was not on a flight plan. Visual meteorological conditions prevailed at the time of the accident. The student pilot reported no injuries. The flight originated from Alexander Field about 15 minutes prior to the accident for a local flight. The student pilot was performing solo takeoff and landing practice during the accident flight. In his written statement, the pilot said that the accident takeoff was his third takeoff. He said that when he was near takeoff speed the, "...tail end of [the] airplane started to fishtail badly...." He said that he attempted to correct and subsequently exited the left side of the runway and hit a snowbank. Postaccident examination of the aircraft by the Federal Aviation Administration failed to reveal any anomalies that could be associated with a preexisting condition.