On April 4, 2004, about 1600 central daylight time, a Schweizer SGS 2-33A glider, N17882, operated by the Civil Air Patrol, piloted by a certified flight instructor (CFI), sustained substantial damage during an off-field landing near Lake Village Indiana. The flight was operated under 14 CFR Part 91. No flight plan was on file. Visual meteorological conditions prevailed at the time of the accident. The CFI and student pilot sustained no injuries. The local flight originated from Lake Village Airport (C98), near Lake Village, Indiana, about 1555. The CFI stated: Shortly before 1600 CDT we departed Lake village Airport for a fourth flight. The takeoff and tow were routine. Approaching for another downwind landing, I observed that we were too low for a normal pattern. I cut the corner and flew over a line of trees and on the downwind side of the trees we encountered significant sink and landed in a soft sandy field. Upon landing we bounced hard and dug the right wingtip into the ground breaking many rivets and bending the wing aft. The student pilot stated: Forecast surface wind was 10 to 12 from N-NW. Actual seemed to be about 15. We had several tow pilots and tow pilot trainees along with glider pilots. Around 1430 hours I was taking instruction from [the CFI] in a glider. We had taken 3 glider rides together earlier in the day. All flights were to about 1000 AGL. ... On the fourth flight we were about 2 or 3 miles north east of the airport (C98). This was the same general area we were in the previous three flights. We performed one steep turn and one slow flight maneuver. We then started back to the airport for a landing. Our altitude seemed to be about the same as earlier flights. About 1-1/2 miles from the airport there is a tree lining running east and west that almost meets a forest that borders the north end of the airport. Just before we reached the east/west tree line we experienced a "sink" as if we went through a down draft. [The CFI] stated "looks like we may need to make an off field landing[.]" He maneuvered the glider past the trees to an open field. He landed the aircraft in the field. The ground had been plowed and was soft. The nose skid dug into the soft ground causing the aircraft to turn left dipping the right wing into the ground where we came to rest. There was damage to the right wing. [The CFI] did a good job of maneuvering the aircraft to avoid trees and obstacles. At 1604, the recorded weather at the Greater Kankakee Airport, Kankakee, Illinois, located approximately 18 nautical miles west of the accident, was: Wind 330 degrees at 11 knots gusting to 18 knots; visibility 10 statute miles; sky condition clear; temperature 10 degrees C; dew point -3 degrees C; altimeter 30.10 inches of mercury. The CFI reported no mechanical malfunctions in reference to the glider. The pilot stated, "The only recommendation would be during training and flight reviews to increase emphasis on keeping very close to the airport when at low altitudes."