Jason Pfaff, a civics teacher at Herman Academy in the border city of Windsor, Ontario. His students are the most diverse group he’s taught in his five-year career, with eight countries represented in just one class period.

Standing at the front of her classroom this past February, the public high-school English teacher Jana Rohrer wrote the words “American Flag” on the board and asked her ninth-grade students to tell her what came to their minds.

Over the past six years Rohrer has used the exercise as part of a lesson to help explain symbolism in Harper Lee’s classic To Kill a Mockingbird. And over the past six years, the students’ answers had become routine: Freedom. Independence. Patriotism.

This time, there were new words mixed among the more familiar responses: Hate. Racism. Danger.

“It was like when you hear a record scratch and the music stops,” said Rohrer, recalling the moment from the classroom exercise. “I was just floored.”

Plenty has been written about the shifting relationship between the U.S. and its allies, including Canada, Great Britain, and Germany, since Donald Trump’s presidential election. But it’s not just playing out during geopolitical summits and trade negotiations. Trump’s influence is also a focus in schools, including Rohrer’s classroom in this modest border town on the Canadian shores of the Detroit River.

Multiple definitions of a so-called “Trump Effect” have emerged over the past 18 months or so, attributed to everything from stock-market gains to reports of increases in bullying and incidents of racial and religious-based hate crimes. More than 10,000 educators participated in a non-scientific online survey conducted by the Southern Poverty Law Center shortly after the presidential election, with over 90 percent of respondents saying the results of the election had negatively affected their students’ mood and behavior. And 80 percent described “heightened anxiety and concern on the part of students worried about the impact of the election on themselves and their families.” More recently, an investigation by BuzzFeed found examples from dozens of school districts nationwide of students using Trump’s own words to bully their classmates.