The flight instructor reported that during landing approach the airplane was low, slow and drifting to the left of the runway. He took control of the airplane and attempted a go-around maneuver but the airplane settled into tall grass to the left of the runway. The flight instructor reported no preimpact mechanical malfunctions or failures of the airplane. The student pilot reported that during the landing approach the flight instructor told him that the approach speed was too low. At that point, the flight instructor took control of the airplane and attempted a go-around but a gust of wind pushed the airplane to the left side of the runway where it touched down and bounced. The airplane subsequently impacted the side of a ditch bank and came to a stop. The airplane sustained substantial damage including a separated landing gear, firewall damage, and bending of the aft fuselage.