"There was some angry reaction about it," said principal Jeff Bruce. "The community is probably going to do a petition to have him removed."
He said Corrections officers told him on May 26 that the offender would be moving into his community the next day.
Corrections northern operations director Lynette Cave said the man was a "very high risk of imminent violent offending" and the department tried to get the High Court to grant a Public Protection Order (PPO), meaning the man would have had to live at a secure facility on prison grounds.
The High Court refused the application and issued a seven-year Extended Supervision Order (ESO) instead.
As well as 11 standard conditions, the Court imposed a further 10 interim special conditions which will remain in force until Corrections applies to the Parole Board for them to be imposed on a permanent basis.
"Public safety is our primary priority," Ms Cave said.
"This offender is subject to monitoring by two staff at all times. He is living at an address that includes locks, alarms and a two metre high fence. He is subject to electronic monitoring and is not able to leave the residence without the permission of a probation officer. His address does not overlook the street and is around 350m away from the school."
Is Mangere becoming a dumping ground for such people, that is the concern of the community.
Mangere MP Su'a William Sio said the decision not to impose a PPO should be appealed.
"The department needs to appeal this and the Minister [Judith Collins] needs to make sure that appeal takes place," he said.
Ms Collins said the law did not allow her to give directions about individual offenders, but she said: "In general, I will expect the department to apply for a PPO in cases where it is appropriate, and likewise to consider appealing unsuccessful applications if it is appropriate in the circumstances and in line with legal advice."
Robert Kumar, who has two daughters at Jean Batten School, said the community was struggling to make sense of why a high-risk offender had been placed close to a school and where he has no connections.
"He is a high-risk sex offender being kept in Mangere, where he has no relatives or links to anyone. So why bring him to Mangere? And why keep him in the vicinity of the school?" Mr Kumar asked.
"Is Mangere becoming a dumping ground for such people, that is the concern of the community."