An Auckland man's decades-long teaching career has come to a standstill after allegations of sexual assault.

The charges have been thrown out, after three 11-year-old schoolgirls admitted they made stories up to get him fired.

After 40 years as a teacher, 27 of which were spent at the school, he was dismissed within a day of the false claims being made.

NZEI national secretary Paul Gaulter told Mike Hosking the situation is as a tragedy.

"I'm not sure how you put all the pieces back together again for this person, and obviously NZEI would support that, but I just can't see how that will be recovered.

"I think it's tragic."

LISTEN ABOVE AS PAUL GAULTER SPEAKS WITH MIKE HOSKING