Reriti used to teach at Natone Park School in Porirua.
Prosecutor Dale LaHood today said aggravating features of Reriti's offending included the "vulnerability" of the victim.
The boy was especially vulnerable at the time, Mr LaHood said, because one of his parents "was extremely unwell".
"Far from being a compassionate supporter" of the boy, Reriti manipulated him, the prosecutor said.
"The breach of trust in this case is extreme."
Reriti, he said, betrayed her duties as a teacher, a leader, and a deputy principal.
Mr LaHood said Reriti manipulated the boy emotionally.
"The real harm [to] this victim won't be known for some time."
Gender "shouldn't be a factor"
The starting point for Reriti's punishment should be 14-15 years in jail, the prosecutor said.
He suggested Reriti's gender shouldn't mean she should escape the sort of punishment a male teacher found guilty of child sex offences would face.
Mitigating features possibly included Reriti's lack of previous convictions, he said, but the length of her offending against the boy made this arguably irrelevant.
The offending continued until 2014.
Reriti's lawyer Stephen Iorns said the disgraced teacher suffered from "serious psychological and psychiatric illness".
There was no escaping the fact "traumatic" situations she'd experienced when younger, and her recent mental state, contributed to the offending, he said.
However, he described Reriti as vulnerable, and said a long jail term would not be good for her.
"Prior to this offending, Miss Reriti was on track to have a very impressive career."
But now, he said, "her career is over".
Justice Mark Woolford equated some of Reriti's offending with rape. He said the charge of unlawful sexual connection carried a penalty of up to 20 years' imprisonment.
He reminded the court that the victim was only 10 when the offending started, at a secluded area the teacher drove the boy to.
"You lay on top of him and kissed him as well as asking him to kiss you..."
Further visits to "secluded areas" followed.
"This occurred reasonably regularly," the judge said.
For these offences, she was found guilty of doing an indecent act.
But the offending escalated from kissing, culminating in sexual intercourse.
"Because a woman cannot be charged with rape" these incidents all resulted in charges of unlawful sexual connection, the judge said.
"A scar" on their lives forever
The boy, now in his mid-teens, made a victim impact statement, Justice Woolford said.
"He feels that his childhood has been taken from him and struggles to see how anything positive can come out of what has happened."
The boy felt betrayed, and his entire family felt Reriti's actions would be "a scar" on their lives forever.
"It has taken a toll on his family who have all felt the strain and the stress of these proceedings."
The court heard the boy was also disgusted after recalling sexually explicit texts Reriti sent him.
"He felt sick at what you said to him, and realising how you had control and manipulated him," the judge added.
"Some of the texts were extremely sexually explicit. You told him you loved him. You also requested naked pictures of him."
If the boy didn't do as commanded, the teacher would threaten him.
"You would threaten to report him to police."
Reriti was guilty of a gross breach of trust that would have long-term impacts on the boy, the school, and the community, the judge said.
"You have ruined that trust and have caused the victim to be suspicious of female teachers generally."
"Nothing in this case mitigates this offending."
Reriti showed no remorse or understanding of the offending, Justice Woolford said.
Reriti gasped and cried as the verdicts of "guilty" were read out last month.
During the trial, she accused the boy of being a liar and "manipulator".
Justice Woolford acknowledged Reriti was mentally unwell, and said her offending was less pathological and degrading than in some similar cases.
"It reflected a perturbing view that you were capable of [having a relationship] with a 10-year-old boy."
For the sexual violation charge, Reriti was sentenced to 10 years and six months in jail.
For indecent assault, she was sentenced to three years' imprisonment.
For the other offences, she was sentenced to eight years' jail, to be served concurrently.
There was no audible emotion from Reriti or the public gallery when the sentence was read out.
A conservative lobby group welcomed the sentence but said rape laws should be updated to remove the "gender inequality" which prevented Reriti from being charged with rape.
"This sentence sends a strong message that gross breaches of trust will receive the full weight of the law," said Bob McCoskrie, Family First national director.
"However, we would question what mitigating circumstances existed which allowed the sentence to be reduced from the prosecutor's starting point of 14-15 years. This offending was calculated and manipulative," Mr McCoskrie added.