According to the student pilot, he was performing a full stop landing from the left seat with his instructor in the right seat. During the flare, a sudden gust of wind "pushed the airplane to the left" and the instructor took the controls. The instructor pilot also reported that a sudden, heavy gust of wind was encountered, and the airplane "started ballooning up" and turned "drastically" to the left. The instructor attempted a go-around; however, the airplane was already at low altitude and it collided with the ground. The airplane impacted hard on the grassy area adjacent to the runway, breaking off the nose gear. Federal Aviation Administration inspectors reported that substantial damage resulted to the airframe's left and right wings. The instructor pilot reported that there were no mechanical problems with the airplane at the time of the accident. Although there was no weather reporting capability at the landing airport, gusting wind conditions were reported about 18 miles to the northwest.