Stephen Wilkinson attended Boynton Secondary School, which became Hall Garth School in Middlesbrough, - scene of Monday's attack - when it merged with adjacent Hustler Secondary School.
Nikki Conroy, 12, was killed in front of her classmates and her friends, Michelle Reeve and Emma Winter, both 13, were wounded.
Mr Wilkinson, of Caversham Road, Easterside, Middlesbrough, was taught in classroom E23 where the attack took place, former fellow pupils said. One said Mr Wilkinson, 29, was taught by Graham Nellist, the maths teacher forced out of the room during the attack.
Mr Nellist's wife, Marilyn, confirmed her husband would have been at the school between the mid- 1970s and 1981, when Mr Wilkinson was there, but 'he has no recollection of him at all'.
Mr Wilkinson is remanded in custody charged with Nikki's murder and the attempted murders of Michelle and Emma.
A helpline which has taken more than 100 calls already is to continue through the Easter holidays. The Cleveland County Council helpline numbers - 0642 262933/4/5 - will be staffed between 8am and midnight and there will be an answerphone service through the night telling callers how to get help and support.Reuse content