A Dallas-area Richardson High School English teacher was arrested and charged with sexual assault this weekend after his 16-year-old student reported that he was harassing her via text and email. James Quigley, 34, tried to convince the student to sign a written contract promising her good grades for sex, according to cops.

WFAA reports:

Quigley gave the student a "written contract" stating he would award her with a grade of 85 or higher in his class if she didn't tell anyone about their relationship, the student said, according to police.

Cops say Quigley was worried about his wife, who is also a teacher at Richardson High, finding out.

While the student never signed the contract, she did tell cops she had sex with Quigley twice at her home over the summer. The student's mother reported that Quigley has been harassing her daughter, even going so far as to park in front of her house "on multiple occasions for no reason."

Quigley is being held on $100,000 bond.

[Photo via WFAA]