A twisted former New Jersey second-grade teacher will spend at least four years behind bars after she admitted to having an “emotionally and morally damaging” affair with a teen girl at her charter school.

Lauren Coyle-Mitchell, 36, was sentenced Friday after she copped to having oral sex with a 15-year-old student at Dr. Lena Edwards Academic Charter School in Jersey City three years ago, law enforcement sources told The Post.

She will spend at least four years and three months in state prison on charges of aggravated sexual assault and endangering the welfare of a child.

At her plea hearing in Bergen County Superior Court in January, the Lyndhurst woman admitted to performing oral sex on the eighth-grade student once at her home in 2015, saying the affair began with explicit text messages.

As her firefighter husband looked on in the courtroom, the married woman conceded the relationship was “emotionally and morally damaging,” according to NorthJersey.com.

Coyle-Mitchell was first arrested and charged on June 22, 2015, after teachers at the charter school went to local police, claiming the teacher and student had inappropriate contact during a field trip to Washington, DC.

She was arrested again a month later for trying to call and text the girl, breaking a court-issued no-contact order, NJ.com reported, and was charged with contempt of court.

As part of her plea deal, Coyle-Mitchell will be eligible for parole in four years and three months after serving 85 percent of her sentence — but faces lifetime parole supervision and must register as a sex offender under Megan’s Law.

The State Board of Examiners — New Jersey’s state teacher licensing authority — voted to suspend Coyle-Mitchell’s certificates on May 12, 2017.

She is permanently prohibited from making contact with the victim and will never be able to hold a government job again.