The student pilot had finished his flight lesson and was returning solo to his departure airport. He observed the windsock and noted that the wind was directly down the runway and approximately 15 to 20 knots. The pilot said that as he entered the flare, he was slow and the left wing stalled, then dropped, and, the left wing and main landing gear touched the runway. The student pilot applied power and the airplane ended up approximately 90 degrees to the runway and 8 feet above ground level, off of the runway surface. The left wing then collided with the windsock pole and sustained substantial damage. No mechanical anomalies were noted.