The pilot in command reported that the purpose of the flight was for continuation hover and taxi training for the student. The student had previously flown two hover flights. The weather was fine, and the flight had progressed for approximately 30 minutes.
The student's handling ability had improved to point that he was able to a hover over a fixed position on the ground. He was hovering the helicopter approximately 2 ft above the ground, when it began to yaw to the right and sink. The instructor told the student to apply left pedal, however, before the student or instructor could take recovery action, the tail rotor contacted the ground. The helicopter pitched up and fell back on the ground on the left side. After completing the emergency shut down checks, both the instructor and student were able to egress through the broken nose bubble without injury.