Sir, - I read that both the Junior Certificate and Leaving Certificate examinations could be in serious trouble because of threatened actions by teachers. It has been suggested by parents' groups that parents should take the place of teachers in supervising these exams. I think it would be better idea if colleges' and universities' exam invigilators could be used. All of the colleges train people to supervise their exams in May and June and these would be ideal candidates to replace the teachers. - Yours, etc.,Gregory Noone, Wicklow.