Claire McDonnell, 22, is one of four women among almost 60 men in a graduate science and finance program at the University of Iowa.
"Some of us girls have the top standings in the program, and no matter how experienced we are, none of the men seem to take us seriously," McDonnell told BuzzFeed News.
Earlier this week, as she was on a video call for a commercial underwriting group project, she began recording because her male classmates were repeatedly interrupting and dismissing her ideas. At first, she said, she only meant to send the video to a friend and another woman in the program.
But she watched the video back and thought it was such a great example of "how often this happens to women in a male-dominated field," so she posted publicly on her TikTok on Tuesday. There, it quickly went viral, and it's now been viewed over 2.4 million times.
"Live footage of a woman in STEM," she captioned the video. In it, she's seen attempting to pitch in and provide suggestions but becomes frustrated when her group project partners seem to steamroll past her.
McDonnell said the irony of that incident was that she had the most IRL work experience out of all her classmates in the field covered by the assignment — but no one seemed to value it.
"When I recorded that, it was just funny because I've worked in commercial underwriting for years, and [the assignment] was the same thing I did in that role," she said. "I have the most experience [out of] anyone."
McDonnell said the TikTok is just one example of the sexist environment she's grown accustomed to in the department, and in the industry at large.
"This happens on a daily basis," she said. "There would be an assignment we [the other STEM women] would help other classmates with, and they would take credit for it. If we present an idea, whether it's theoretical or any type of opinion, it's always like they're very hesitant to believe it."
"And if they do believe it, then they take the credit like, I already knew that, and repeat it to other people and claim it as their own."
She said in one instance last year with a professor in the department, he approached her and another woman colleague and asked them, "Ladies, do you understand what's going on?" about the class material.
BuzzFeed News has reached out to the University of Iowa and the department for comment on her videos.
McDonnell added that the attention she does get from her male classmates is "creepy," with some brazenly messaging her about her looks and others asking her out.
Her TikTok of the brief interaction in school has resonated with people outside of STEM, and university, and the reactions are visceral.
"THIS HAPPENS WAY TOO OFTEN AND IT'S NOT OKAY!!!!!" one person commented. "This made my skin BOIL," said another. "The way I am seething with rage," another wrote.
Some advised McDonnell to continue talking over them unapologetically.
"Literally keep talking. Do not stutter. Do not pause. Speak as if they aren't saying anything," a top commenter wrote. "Keep talking until they realized they've interrupted you," another person echoed.
McDonnell said she did not expect it to go viral, but she's also not surprised it did because so many women could relate. As far as she knows, none of her male group project members know about the TikTok — or at least have reached out to her since it's gone viral.
"You can't change the way they view women overnight, but stepping back and listening. ... If I have something to say, just listen," she advised any of them who may be reading this article. "And not just listen, but implement what I and other women are saying."
"From an outside perspective, you almost have to laugh at how awful it is," she added. "It's a very serious issue that brings to light how many women experience it. It's something that needs to change. Men have to be willing to make those changes."