On October 5, 1997, about 1530 eastern daylight time, a Cessna 152, N89627, was substantially damaged as it nose over after departing the runway during landing at the Chandelle Estates Airport (0N4), Dover, Delaware. The certificated student pilot was not injured. Visual meteorological conditions prevailed and no flight plan was filed for the instructional flight conducted under 14 CFR Part 91. The student pilot took off from 0N4 and practiced flight maneuvers for 45 minutes. He flew to the Smyrna Airport, Smyrna, Delaware, for two landings, and returned to 0N4 for additional landings. The pilot stated that he had already completed two landings and was executing the third one when the accident happened. Runway 04 was 2,533 feet long with a 539 foot displaced threshold. The pilot recalled that on final everything was the same as the two previous landings, except he was a little higher and a little faster. With 30 degrees of flaps, the student pilot remembered pushing forward on the yoke and the airspeed increased to about 70 knots. His plan was to touch down by midfield, or abort the landing. The airplane bounced at midfield, settled back to the runway, and the pilot applied heavy braking. The airplane skidded off the end of the runway into a freshly plowed garden. The nose gear sank into the soft ground, collapsing, and the airplane nosed over, coming to rest inverted. A Federal Aviation Administration Inspector examined the wreckage. The examination revealed that the nose gear strut broke off, the fire wall was damaged, and both wings incurred spar damage. The pilot reported that he did not have any mechanical problems with the airplane.