The glider instructor was giving an introduction flight. During the tow-plane assisted launch, the glider's air brakes were inadvertently deployed. The tow plane was unable to obtain a positive rate of climb, so the tow-plane pilot signaled for a glider disconnect. The glider pilot released the glider from the tow plane, about 175 feet above the ground. After the release the pilot made a 125 degree right turn to land on an adjacent taxiway and touched down with a high descent rate. During the landing the glider sustained substantial damage to the right wing, right aileron, and fuselage. The pilot sustained minor injuries. The passenger was not injured. The pilot reported no mechanical malfunctions or failures with the glider prior to the accident that would have resulted in abnormal operation of the glider. In addition, he reported that he accomplished a pre-launch checklist prior to the flight and that the launch was more turbulent than normal. He remarked that the accident could have been prevented if he would have landed straight ahead instead of making the right turn. Witnesses on the ground reported seeing the air brakes deploy during the launch.