The student pilot stated that the purpose of the solo flight was to perform maneuvers in the local practice area in preparation for an upcoming checkride. After performing a series of maneuvers, the pilot returned to the airport and was cleared to land on the active runway. The pilot noted that during the landing flare she realized the airspeed was higher than desired and responded by manipulating the throttle control. During the landing, the airplane touched down hard and bounced back airborne. The airplane continued to bounce down the runway about 3 to 4 times before coming to a stop. As a result of the impact, the airplane incurred substantial damage to the firewall. The pilot reported no preimpact mechanical malfunctions or failures with the airplane that would have precluded normal operation.