On October 22, 1993, at 1030 central daylight time, a Cessna 150L, N17056, sustained substantial damage near Athens, Texas, following a loss of control during the landing roll. The student pilot did not receive injury. Visual meteorological conditions prevailed for the local instructional solo flight. During interviews conducted by the Federal Aviation Administration inspector and the investigator in charge with the operator, the controller, the flight instructor, and the student pilot, the following information was revealed. The dual instructional flight departed Tyler, Texas, at approximately 0910 for a local flight to the Athens Municipal Airport, Athens, Texas. Following a series of touch and go landings, the flight instructor exited the airplane and released the student pilot for his first solo flight. The winds were reported from 020 degrees at 7 knots. Approximately 20 seconds into the landing roll on runway 35 the airplane began to turn left. The solo student applied right aileron and right rudder but the airplane exited to the left of the runway. The right main gear struck a concrete wall of a drainage ditch resulting in its separation.