On October 20, 2006, about 1620 eastern daylight time, a Cessna 150L, N10772, registered to and operated by a private individual, experienced an in-flight loss of control during a go-around at the Umatilla Municipal Airport (X23), Umatilla, Florida. Visual meteorological conditions prevailed at the time and no flight plan was filed for the 14 CFR Part 91 instructional flight from Orlando Sanford International Airport, Orlando, Florida. The airplane was substantially damaged and the certified flight instructor (CFI) was not injured while the student pilot sustained minor injuries. The flight originated about 1530, from Orlando Sanford International Airport. The CFI stated that after takeoff the student performed airwork while en route to X23. He (CFI) demonstrated the first landing and the student performed the approach for the 2nd landing on runway 36. The flight remained in the traffic pattern and after turning onto final approach, the student was too high. A go-around was performed and the airplane remained in the traffic pattern for runway 36. While on the downwind leg when the flight was abeam the approach end of runway 36, carburetor heat was applied then the engine rpm was reduced to 1,700. The student also lowered the flaps to the 10 degree extended position. The flight continued on the downwind leg for another 30 seconds then turned onto the base leg where the flaps were extended another 10 degrees and the airplane was slowed to 80 miles-per-hour. The flight turned onto final approach where the flaps were lowered another 10 degrees (30 degrees extended), and he asked the student how we was doing. The student replied that he was slightly high and lowered the nose which caused an increase in the indicated airspeed. The flight continued on final approach and crossed the landing threshold fast causing the airplane to float. He told the student to go-around, and the student applied full power. The airplane "...settled then started to climb." The flaps were raised to the 10 degree extended position, and the airplane then banked to the right, the nose pitched down, and the airplane impacted the ground. The CFI further reported that based on his postaccident observation of the flaps (left flap extended and right flap retracted), he believes a malfunction of the flaps caused the airplane to roll to the right. During an interview with an FAA inspector the day after the accident the CFI was asked if the airplane stalled and he responded that he did not think so but was not sure. The student reported that with respect to the accident approach and landing, he realized the airplane was too high so he applied power and removed carburetor heat to perform a go-around. When the airplane was over the departure end of runway 36, or approach end of runway 18, "...it felt like there was a sudden swift push from the left side of the aircraft. Which caused the aircraft to turn 20 to 30 degrees to the east 'right'." He did not recall any other events until he was removing his seatbelt and freeing his pinned legs. Following recovery of the airplane, it was examined by a representative of the airplane manufacturer with FAA oversight. Examination of the airplane revealed the outboard portion of the left wing was displaced up, and the leading edge outboard of the landing light was displaced aft. Impact damage was noted to the inboard leading edge of the right wing, and the right wingtip was separated. Both flaps and ailerons remained attached, and flight control continuity was confirmed for roll, pitch, and yaw. Further examination of the flap system revealed the left flap was in the down position. The push/pull rod between the left flap and actuating bellcrank was attached, and both cables were connected at the bellcrank. The forward cable was continuous from the left bellcrank to the right flap bellcrank, but the rear flap cable was fractured approximately 40 inches from the flap bellcrank. Visual examination of the fractured cable revealed the fracture was consistent with tension overload failure. No corrosion was noted on the cable in the fracture area. The right flap was up, and the flap actuator located in the right wing was also in the retracted position. The push/pull rod between the right flap and actuating bellcrank was attached, and both cables were connected at the bellcrank.