The pilot was receiving transition training from the flight instructor. After departure they practiced maneuvers and then flew to a different airport where the pilot performed a full-stop landing. While waiting to depart the flight instructor discussed the steps for a go-around. After departing, the pilot remained in the airport traffic pattern, and while on final approach with full flaps extended the flight instructor noted the airplane was a “little high.” The pilot rounded out high and the airplane was “really slow,” so the flight instructor called for a go-around. The pilot described that as part of that procedure, he intended to raise the flaps to 50%, but he inadvertently moved the flap selector to the fully retracted position. After immediately recognizing what he had done he repositioned the flap selector to 50%. The airplane subsequently contacted the runway, with the pilot increasing the engine power to full. The airplane then drifted off the left side of the runway and the flight instructor asked to take control while the stick shaker and stall warnings were occurring. The airplane’s right wing then impacted the ground and it slid off the runway onto grass coming to rest upright. The airplane’s structure firewall and engine mount were substantially damaged during the accident. Neither the pilot nor the flight instructor reported that there were any preimpact mechanical malfunctions or failures of the airplane that would have precluded normal operation.