Newlywed Christopher Reen was arrested by Humberside police and has been bailed while police and council staff investigate.
Reen, 30, who looked after kids as a stand-in when teachers were off, also runs his own martial arts company. He has been working with the education department to teach schoolkids self-defence.
A parent whose child goes to the school near Bridlington, East Yorkshire, said: "Are these people not aware what can happen to them? It should be drilled into them not to mess with pupils."
Earlier this year we revealed how three paedophile teachers ran a BIBLE CLUB to groom victims at the 1,500-pupil school.
Ian Blott, 55, and Steven Edwards, 35, were jailed after courts heard Blott had seduced a 15-year-old while Edwards had affairs with three young girls.
Third teacher Terry Mann, 45, got away with his affair because the GCSE student had left school and refused to give evidence against him.
But he has since been given a 12-month suspended sentence for having sex with an underage girl at another school.
Teaching assistant Lindsey Jane Collett, 26, also escaped jail because her relationship with a 16-year-old boy stopped short of sex.