Kate Mara’s latest role is of a high-school teacher who has an affair with her underage student — and it made her realize just how widespread this problem is.

“We had it on Google Alerts,” Mara, 37, told The Post of illicit teacher-student trysts. “The amount of real-life stories that we’d see on a weekly basis was quite overwhelming. This type of predatory relationship happens much more frequently than I think most people would expect,” she said.

This encouraged her to move forward with “A Teacher,” a boundary-pushing project that premieres Nov. 10 on Hulu. The 10-episode limited series, which Mara stars in and also produced, follows 30-something Claire as she lands a new job teaching English at a suburban Texas high school. Soon, she becomes entangled with one of her students, a 17-year-old senior named Eric (Nick Robinson, 25, best known for “Love, Simon”).

What begins as innocuous after-school tutoring quickly evolves into a secret romance. Claire, who is married, has to find ways to explain her strange behavior to her husband, while Eric tells his friends that he’s seeing an older woman — from the local college.

Mara said it was a challenge to portray someone so unsympathetic: “Playing someone who is an abuser — who uses her position and her power to manipulate someone — is not something that I would say is an easy thing to do.”

It felt particularly daunting, she said, given that she’d just given birth to her daughter when filming started on “A Teacher” in 2019. Mara, who’s the older sister of Rooney, 35 (and aunt to her baby, River, with Joaquin Phoenix), married her “Fantastic Four” co-star Jamie Bell, 34, in 2017.

She said the production team and cast made her return to work as a new mom feel as comfortable as possible.

“There’s some very intimate scenes we had to shoot, and I had just had a baby three months before, so it could have felt vulnerable and scary. But it didn’t feel that way at all, because I had incredible support. Nick [Robinson] is awesome. He’s a true professional.”

“A Teacher” is based on a 2013 movie of the same name, written and directed by Hannah Fidell, who also helmed the miniseries. Mara said Claire and Eric are not based on any real people, though she’s well aware of the various female teacher-male student relationships that have made headlines over the past few years. Recent cases include then-26-year-old Texan Sarah Fowlkes, who turned herself in for improper relations with a 17-year-old student in 2017; 27-year-old Floridian Stephanie Peterson, who was arrested in 2018 for alleged relations with a 14-year-old; and 22-year-old high-school science teacher Hunter Day, who was arrested for alleged sex with a student in 2017 in Oklahoma.

Mara, who is best known for her roles on “House of Cards” and “24,” said she was attracted to this story because she was interested in showing “both perspectives”: of Eric, the victim, as well as Claire’s.

“Although we know her choices are wrong, we wanted to show the human side of her as well,” Mara said of her character in the show. “For example, everyone can relate to feeling lost at some point in their lives and wanting to be seen. That does not give any sort of justification to her choices at all — but it’s finding those relatable characteristics that’s important.”

The show does not portray Claire as a one-dimensional monster. Rather, it delves into the personal struggles that impact her poor decision-making, such as her crumbling marriage. For Mara, that was key to digging into Claire’s complicated psychology.

“I like that [the show] exposes the gray area of consent and power dynamics and grooming,” Mara said. “What I was excited to explore was highlighting the lies that my character Claire told herself in order to justify behavior that she knew was wrong the entire time.”