Crown prosecutor William Fotherby said on the day Miki received his supervision order, he took a day off school to go to court and returned to the school the next day.
"This is audacious offending by a talented - in the wrong way - individual.''
He said not only did Miki use fake qualifications, he also stole an identity to avoid detection by the authorities.
Mr Fotherby said Miki had been paid $159,000 for working as a teacher.
"Schools had to go to their community and say: 'Look, we've exposed your child to a sex offender and parents have had to ask their children very difficult questions'.''
Miki's lawyer Ron Mansfield said the sentencing should not be inspired by "emotive fear''.
"There has been no [new] offending of a sexual nature, nor an indication to do so.''
Mr Mansfield said Miki worked hard and contributed to the schools in a positive way, despite not having any formal qualifications.
Judge Claire Ryan said while there were no allegations of fresh sexual abuse, schools had used words like "trampling their mana and wairua''.
She took into account Miki's early guilty plea to save those people having to come to court to give evidence.
Judge Ryan questioned why Miki went back to teaching when he had skills that could have been applied to other jobs.
"One can say there is no evidence that he did anything, but one can also say there is no evidence that his intentions were entirely innocent either.''
After giving Miki a discount for his early guilty plea, Judge Ryan reached an end sentence of four years, one month and two weeks in prison.
Miki's case is the subject of a ministerial inquiry which will look into how he was able to elude authorities.
Another case, revealed by APNZ last month, has been added to the inquiry. That involved a convicted child sex offender being hired as a teacher, despite the school knowing of the conviction.
Miki's elaborate efforts to avoid detection were revealed in court documents today.
According to the police summary of facts he used false documents and legally changed his name to escape his past.
He also told a school he had two degrees from the University of Rochville in the United States.
Miki's past caught up with him at another school when the principal ran checks.
According to the summary, when confronted by the principal, he said had a twin brother who was responsible for the convictions.
Miki was fired after the police became involved in another matter.
He also used the name of a man he knows with teaching qualifications who was living in Australia.
Miki successfully applied to the Department of Internal Affairs to change the man's name to one of his aliases before approaching the Teachers Council for registration.
With a new birth certificate, he was able to get the real teacher's record transferred into the name of his alias.
Miki then took a job at an Auckland primary school and, according to police, took a lot of sick days, claiming he had a brain tumour.
He was caught only after he came clean to his probation officer.
Miki has previous convictions including 62 for fraud and convictions in Australia.
