Flight Instructor reported solo student pilot while attempting to land losing directional control resulting in the aircraft's wing striking the ground.

Narrative

I am a flight instructor; and the student pilot involved in this event is Person A.At the time of the event; I was overseeing Person A solo flight. Although I oversaw this particular flight; Person A had been trained and endorsed for solo by another instructor at our flight school; who was on leave at the time.Per our school's policy; if a student has not conducted a solo flight in over a month; a 'confidence flight' with an instructor is required before they may fly solo again. Because this was Person A first solo flight; and it was also my first time flying with her; to ensure her readiness; I conducted a thorough 1.3-hour confidence flight beforehand. During this flight; I evaluated all required Private Pilot-level maneuvers; including steep turns; slow flight; power-off stalls; power-on stalls; and ground reference maneuvers. Based on the stage of her training; Person A performance was satisfactory.To further assess consistency in her landings; I also had her fly five laps in the traffic pattern; which included three normal/crosswind landings; one go-around; and one simulated engine-out landing. Person A executed the go-around and all four landings safely without any prompting or intervention from me. I concurred with her primary instructor's assessment that she was ready and safe to conduct solo operations. I also verified that she had all the required endorsements and documentation for solo flight.Before dispatching Person A; I asked if she felt ready and confident. She responded affirmatively; and I dispatched the solo flight.During the third landing; Person A initiated the flare slightly too high; causing the airplane to level off approximately 5 to 7 feet above the runway. As airspeed decayed; the airplane descended more quickly and landed firmly. My view of the touchdown area was partially obstructed by another aircraft; but according to Person A account; after landing; she momentarily lost directional control and the right wingtip of the RV-12iS contacted the pavement. She promptly regained control and taxied the airplane safely back to the hangar.Afterwards; I spoke with all the instructors at the flight school; including Person A primary instructor; and recommended that we further improve and standardize our approach to teaching landings. Specifically; I suggested that our training should emphasize not only proper flare timing but also how to recognize and recover from a high flare before touchdown. Key techniques to reinforce include:1) Adding power to arrest the descent.2) Freezing the pitch to prevent further ballooning.3) Resuming the flare once the descent recommences.4) Aborting the landing if necessary.I have used these techniques with my own students to great effect.