The elite Brooklyn Technical HS is gaining a reputation for sleazy teachers.

A fourth staffer in two years has engaged in an “inappropriate relationship” with a student, investigators charge.

English teacher David Lo, 39, bombarded a girl with e-mail messages, nudging her to meet him outside of school — and to send him “fitness” photos of herself, the Special Commissioner of Investigation found.

“How did your workout go? Any recent workout pics?” Lo asked the girl.

“Let’s see a daily pic of the day from you!” he begged in another message.

Lo’s student first approached him in June 2015 to request “extra credit.”

In a later face-to-face conversation, Lo told the girl “they could not communicate by e-mail because a teacher lost his job for that contact,” says an SCI report.

Lo proceeded to e-mail the girl from his personal account. The two exchanged more than 100 messages over the summer before the girl “expressed concern” to authorities, SCI reports.

Among Lo’s missives:

“How did you look when you were younger? The same? Different? How did you look when you first entered high school? I remember the first day when you walked up to me.”

“Long time no talk! Do you need to get your phone fixed? I thought that you were too busy for me and would not write me back ever again! . . . Let’s talk more than once a week!”

“Do you want to run tomorrow? I get out at 2. I can meet you at 2:45 pm . . . What do you say? You have my number. If you [want] to confirm plans tomorrow let me know. What are you doing today?”

Lo invited the girl to go with him to a concert by rapper Flo Rida in Staten Island, which she declined, and “pressured” her to volunteer with him at a race. She registered but did not show up, the report says.

He also asked the girl to communicate with him via “WhatsApp,” a free mobile messaging service, the report says.

Lo, whose salary was $85,793, did not return a request for comment.

The city Department of Education said he resigned last July.

Lo is the latest Brooklyn Tech staffer to get the boot between 2014 and 2016 for improper contact with kids.

Physics teacher Sean Shaynak, now in prison, was busted in October 2014 on charges he sexually abused seven students. The city paid $450,000 to settle lawsuits.

Aide Robert Sutton Jr. sent a student at a school where he previously worked a photo of his penis and video of himself masturbating inside Brooklyn Tech, SCI charged.

Music teacher Marisa Casanave resigned last October after a student’s mom found love notes between her and the boy.

Brooklyn Tech students aren’t surprised by the series of scandals.

Michael Tyutyunik, 17, a junior, said “isolated incidents” are bound to happen in a huge school with 5,500 students.

Others said kids flirt and hang out with teachers to gain an edge at the competitive campus, the alma mater of Mayor de Blasio’s son, Dante.

“Some students will do whatever it takes to get good grades. There’s a lot of pressure here to do well,” said a 16-year-old junior.

And some teachers exploit the competition, students said, citing a current instructor who seems to favor girls.

“My cousin was in his class and he told her to come to after-school tutorial once — and wear a low cut shirt,” said a freshman boy, 15.

“Other teachers know and don’t do anything,” said a 15-year-old female freshman. “Administrators aren’t investigating . . . Some teachers think they can get away with it.”

Longtime principal Randy Asher abruptly left in January to take an administrative DOE post.