On June 8, 2003, about 0830 eastern daylight time, a Cessna 150, N92WA, was substantially damaged during takeoff from Culpeper Regional Airport (CJR), Culpeper, Virginia. The student pilot was not injured. Visual meteorological conditions prevailed and no flight plan was filed for the local solo instructional flight conducted under 14 CFR Part 91. The student pilot initiated a takeoff from runway 04, a 4,002 foot-long, and 75 foot-wide runway. The student pilot stated that during the takeoff roll, he "lost control" of the airplane, and could not maintain centerline alignment. The airplane ran off the side of the runway, and came to rest in a ditch. The student pilot reported there were no wind gusts, and he experienced no mechanical anomalies with the airplane. Examination of the airplane by a Federal Aviation Administration (FAA) inspector revealed substantial damage to the left wing spar. No pre-impact mechanical anomalies were observed. The winds reported at an airport about 20 miles to the northeast, at 0810, were from 020 degrees at 3 knots.