On April 24, 1995, about 1815 eastern daylight time (EDT), a Cessna 150F, N8291S, settled into a marsh area during takeoff from a private field in Napoleon, Michigan. The airplane was substantially damaged. The private pilot was not injured. The sole passenger aboard the airplane received minor injuries. No flight plan was filed, and visual meteorological conditions prevailed for the personal flight. The pilot stated he had been practicing takeoffs and landings at several local airstrips. He then landed at the private field. He reported that after landing, he failed to retract the flaps. During a subsequent takeoff, he stated, that the airplane would not climb after takeoff. It crossed a road and settled to the terrain in a marsh area. Examination of the airplane revealed the wing flaps were extended and jammed in the 40 degree extended position.