On July 12, 2003, about 1022 mountain standard time, a Cessna 172S, N5327G, made a hard landing and collided with a runway sign at the Chandler Municipal Airport, Chandler, Arizona. The airplane was operated by Angel Air, Chandler, under the provisions of 14 CFR Part 91, and it was substantially damaged. The student pilot was not injured during the solo instructional flight. Visual meteorological conditions prevailed at the time, and no flight plan was filed. The flight originated from Chandler about 1016. The student pilot's certified flight instructor (CFI) reported that earlier during the morning she and her student practiced several landings in the traffic pattern. The CFI opined that the student was ready to perform his first solo flight. She exited the airplane and observed the student depart, fly downwind, and make what appeared to be a normal approach to the runway using 30 degrees of flaps. The wind was nearly calm. The student appeared to flare out higher than normal over the runway, and he increased engine power to recover. According to the student, after increasing engine power the desired effect was not achieved, and the nose wheel struck the runway hard. Thereafter, the airplane porpoised 5 to 6 times. The student lost control of the airplane. The airplane veered off the left side of the runway and collided with a runway sign.