On December 4, 2002, about 1715 eastern standard time, a Cessna 172H, N2706L, was substantially damaged during a collision with trees and terrain following a loss of engine power and a forced landing near Leeds, Massachusetts. The certificated flight instructor and the certificated student pilot received minor injuries. Night visual meteorological conditions prevailed for the local instructional flight that departed Barnes Municipal Airport (BAF), Westfield, Massachusetts. No flight plan was filed for the flight conducted under 14 CFR Part 91. According to the flight instructor, the purpose of the flight was to perform a pre-solo evaluation of another instructor's student. The student performed the preflight inspection of the airplane by the checklist under the supervision of the flight instructor. The student pilot checked the fuel gauges and looked in the tanks, but did not "stick" the tanks and confirm the exact quantity. He estimated that each tank was about "three-quarters" full. The fuel samples drained from the wings and the fuel strainer were absent of water and debris. The student pilot performed the engine start, run-up procedures, and before-takeoff checks, and all indications were normal. He then flew out to the local training area and performed steep turns. The flight instructor noted some minor deficiencies in the student's technique, and demonstrated the use of pitch and power to smooth the maneuver. They then transitioned to minimum-controllable-airspeed maneuvers, then to power-off stalls. During a stall recovery, the flight instructor noticed a reduction in engine power. He adjusted the throttle, mixture, and carburetor heat controls but the engine stopped producing power, and the propeller stopped completely. During the subsequent descent, the flight instructor contacted air traffic control (ATC), declared an emergency, and selected a field for the forced landing area. The airplane struck trees prior to the field, descended to the ground, nosed over, and came to rest inverted. The airplane was examined at the site by a Federal Aviation Administration (FAA) team of inspectors. The inspector-in-charge said there was only a faint odor of fuel, and there was no evidence of fuel spillage at the scene. During recovery of the airplane, both wings were removed. The right fuel tank was intact and contained no fuel. An attachment screw for a wing tank access panel punctured the left tank during the accident sequence. There was no fuel in the tank, and no evidence of leakage through the hole. After recovery, the engine was rotated by hand, and continuity was established through the powertrain and valvetrain back to the accessory section. Both magnetos "snapped" during rotation. The fuel line to the carburetor was dry, and the carburetor contained no fuel. The flight instructor held a commercial pilot certificate with ratings for airplane single engine land, and instrument airplane. He held a flight instructor certificate with a rating for airplane single engine land. His most recent second-class medical certificate was issued May 14, 2002. The flight instructor reported approximately 1,200 hours of flight experience, 550 hours of which were in the Cessna 172. The student pilot was interviewed by telephone. His account of the events was consistent with that provided by the flight instructor. The student pilot was issued a third class medical certificate on August 7, 2002. He reported 14 hours of flight experience, all of which was in the Cessna 172. Both pilots reported there were no anomalies with the handling and performance of the airplane prior to the loss of engine power. The student pilot added that at one point during the flight he noticed the fuel gauges "bouncing between the one-half and three-quarters" position. He also noticed a faint odor of fuel, but didn't report it to the flight instructor. The engine was removed from the airplane, and taken to East Coast Aero Tech, where it was mounted on a donor airframe and tested. The engine ran without any problem. At 1653, the weather reported at Barnes Municipal Airport included clear skies with winds from 340 degrees at 6 knots. Official sunset was at 1621. The moon set at 1640, and was 28 degrees below the horizon at the time of the accident.