On October 17, 1997, at 1720 central daylight time (cdt), a Cessna 152, N68299, piloted by a flight instructor, giving dual instruction to a student pilot, was destroyed when it nosed over during a forced landing onto a plowed field following a total loss of engine power. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 instructional flight was not operating on a flight plan. The flight instructor and student pilot reported no injuries. The flight departed Quincy, Illinois, at 1615 cst. The flight instructor said he had flown the airplane earlier in the day with the student pilot. He said he assigned the student solo flight maneuvers after refueling the airplane so it would depart with 20 gallons of fuel on board. The instructor said the student had flown about 1 hour and returned to the airport. He said he "...went up with her once again to check her status on the maneuvers." The instructor said he "...turned the fuel off to simulate an engine failure." According to the instructor, the student performed the emergency procedures associated with an engine failure. He said he returned the fuel selector to the "ON" position. The instructor said he attempted to start the engine without success. The instructor said that he "...set the airplane up for an emergency landing." He said he "...chose... the best [field] in the area considering the altitude we at and our rate of descent." The instructor said the airplane touched down in the field and the next event he recalled was the student "...calling his name several times." The accident was reported to the NTSB about 2 months after it occurred. The airplane was not available for examination.