THE STUDENT PILOT WAS ON A SOLO-INSTRUCTIONAL FLIGHT IN THE PRACTICE AREA. AFTER SEVERAL CIRCUITS AROUND HIS GIRLFRIEND'S HOUSE (INSIDE THE PRACTICE AREA), HE SET UP FOR A POWER-OFF STALL. ACCORDING TO WITNESSES, HE BEGAN THE STALL MANEUVER AT ABOUT 300 FEET AGL. A VIDEO TAPE ACCOUNT OF THE ACCIDENT REVEALS THAT THE AIRPLANE STALLED, THE THROTTLE WAS ADVANCED, AND THE AIRPLANE ENTERED A LEFT-HAND SPIN. ABOUT ONE TURN OF THE SPIN WAS COMPLETED WHEN THE AIRPLANE IMPACTED TERRAIN IN A STEEP, NOSE LOW ATTITUDE. ANALYSIS OF THE VIDEO REVEALED THAT THE ONLY FLIGHT CONTROL INPUT WAS FULL UP ELEVATOR, WHICH WAS APPLIED THROUGHOUT THE ENTIRE SEQUENCE. THE STUDENT'S LOGBOOK INDICATED THAT TAUGHT HIM TO PERFORM ALL AIRWORK PRACTICE AT 3,000 FT MSL (ABOUT 2,500 FT AGL). THE STUDENT'S LOGBOOK INDICATED THAT STALLS HAD BEEN PRACTICED ON AT LEAST NINE PREVIOUS FLIGHTS (THREE SOLO FLIGHTS).