A flight Instructor reported the student was veering off the runway while taking off; did not relinquish control and the aircraft ran off the runway and struck a runway light.

Narrative

I was instructing a student pilot on his 2nd lesson after a 2 week gap from the first one. We started the aircraft and received a clearance to the active runway; and began our taxi. The winds were strong but not uncontrollable; but my student had difficulty maintaining the taxiway centerline. On a larger deviation to the left; my student reacted by putting in an abrupt full right rudder deflection and applied brake.I declared 'my controls' and my student froze on the controls and failed to follow procedure. By the I was able to get him to respond; the aircraft was past the taxiway edge; and the right main gear struck the light. At this point we notified Tower; completed a circuit on the taxiway to verify function; and took the aircraft back to the ramp for inspection by the Mechanic. The Mechanic verified the dent; inspected for any further damage; and approved the aircraft for continued operation. A flight was then commenced without incident.The training environment brings a lot of unusual reactions to stress; and in the future I will do a better job of re-emphasizing the positive exchange of controls in these early lessons; especially when potentially challenging winds exist.