The student pilot reported that the high-wing airplane in which she had received her initial flight training had been sold, and she had transitioned to the low-wing (accident) airplane. She stated that she acquired 5.9 hours of flight training in the low-wing airplane before she was authorized to solo in that airplane. During the accident landing, she reported that, "My final approach speed was a little higher than recommended and the nose of the plane was pointed slightly left of the centerline upon landing." During the landing roll, the pilot reported that she applied full back pressure and stepped on the brakes hard, but was unable to prevent the runway excursion. After departing the runway to the left, the airplane impacted a ditch. The airplane sustained substantial damage to the fiberglass fuselage structure. The student pilot reported that there were no pre-impact mechanical failures or malfunctions that would have precluded normal operation.