This week’s seventh-grade English teacher — and cheerleading coach — busted for allegedly having a bunch of sex over summer vacation with a 15-year-old male student with is Katherine Ruth Harper.

Harper, 27, taught at John M. Tidwell Middle School in the suburbs of Dallas until she was placed on administrative leave, according to the Fort Worth Star-Telegram.

Also, Harper, 27, is currently eight months pregnant, according to local FOX affiliate KDFW.

Investigators say the sexual relationship between Harper and the teen occurred last summer (during June and July). The sites of their multiple trysts were Harper’s house in Fort Worth as well as the teen’s house in Trophy Club, a comfortable Dallas metroplex suburb.

Romance initially budded when the 15-year-old student and the 27-year-old teacher began a frisky texting correspondence.

Harper knew the unidentified 15-year-old student during his time at Tidwell Middle School. In addition to teaching seventh-grade English there, Harper was a cheerleading coach and a tennis coach at the school, according to the Star-Telegram.

The 15-year-old student had played on the tennis team at Tidwell, KDFW reports.

Sparks flew when Harper paid a summer vacation visit to the student at his home, the police affidavit says.

The teen and Harper started by drinking alcohol. Next, they removed their clothes. Then, Harper allegedly performed an unspecified sex act on the teen.

More meetings followed.

“One thing led to another and she told me to ‘put it in’ and I did,” the 15-year-old student told investigators, according to KDFW.

The pair used their mobile phones to communicate — some 76 times — and to exchange a slew of nude images during the fling.

Police say the 15-year-old male student kept the trove of naked selfies he received from Harper.

The arrest warrant does not connect the 15-year-old student as the father of Harper’s baby.

A pregnancy currently eight months in the making means that the pregnancy would have begun sometime around late July.

School officials had investigated Harper back in September based on a tip but that investigation fizzled. The investigation was reopened in December based on a second tip. This second investigation proved more fruitful.

The police affidavit indicates that a school official asked the student if he and Harper had sex. He allegedly broke down crying and admitted the affair.

Police arrested Harper last week.

She faces a second-degree felony charge called improper relationship between an educator and student.

After her arrest, Harper posted a $15,000 bond and was released from jail.

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