It happened again: the single most contentious and edifying day of the semester, which I look forward to year after year. It’s the session in my editing class where we discuss racial and gender bias in language. And it’s the one in which my undergraduates, mostly blacks and Latinos from the Bronx, do the educating.

Do you prefer black or African-American? I ask them. Latino or Hispanic? Why is it wrong to call Hispanics “Spanish”? Why is the courtesy title “Ms.” neutral in a way “Miss” and “Mrs.” are not? It is OK for a straight person to use the word “queer”?

Overcoming Bias: A Journalist’s Guide to Culture & Context, by Sue Ellen Christian, I asked the class to write about a situation in which an incorrect assumption had been made about them. Though I told them they could also address gender, sexual preference, disability, class, or religion, all 23 of my students wrote about race and ethnicity.

A vast taxonomy of racial nuance and bias emerged, confirming how little appearances reveal, and how much they matter. There was the dark-skinned Dominican who is perceived as black. The light-skinned Dominican who is perceived as Puerto Rican. The light-skinned black who is perceived as Latina but doesn’t mind because people are nicer to her when they think she’s Latina. The light-skinned black who is treated well by Dominicans on her block until she reveals she doesn’t speak Spanish. The biracial (black and Scottish) student, assumed to be Hispanic because, as a co-worker told her, she doesn’t “act black.” The Dominican who received a “compliment” from a man who told her she didn’t look Dominican.

A black man described seeing a white woman clutch her purse as she passed him on the street: “It made me feel sad. She must have had a bad experience,” he wrote, I thought, over-generously. An African-American who “sister locked” her hair is now presumed to be Jamaican. A mixed-race (black/Cuban/Native American) student, surname Diaz, had been placed in advanced high-school Spanish, though his Spanish was terrible.

Then there was the Honduran who is routinely assumed to be Puerto Rican, Mexican or Dominican because “that’s what New York Hispanics are.” The black student who isn’t religious and doesn’t like hip hop or Tyler Perry, whose white friend asked him incredulously, “Don’t you like anything black?” And the student of Puerto Rican descent who doesn’t speak Spanish and has no affiliation with Puerto Rican culture, who notices that when people ask where she’s from, they’re visibly irritated when she says, “I’m American.” This, apparently, doesn’t answer their question.

As usual, the class broke down the social calculus that consistently colors their lives, marveling at each other’s misadventures and confessing their own mistakes. One light-skinned Dominican had angered a Korean pizza server by calling him “Chino” when he ordered. “Here you go, black man,” the server sneered in return, then dressed him down, not because he didn’t want to be addressed by his race, but because no Asian, he said, wants to be mistaken for Chinese. And so the server’s view of blacks on the racial hierarchy was coded into his retaliation for the misnomer.

In April, MTV released a much-discussed survey of millennials about race, concluding, among other things, that although they believe they live in a racially sensitive society, most see bias at play in their lives. This much appears to be true. But the survey itself was biased in its reductivism: It involved focus groups in six cities, targeting 3,000 people. Every American city contains its own racial dynamic based on history, immigration patterns, geography, industry, economics, culture, politics, and a host of other factors. Six cities can’t reflect the gradations of American diversity, urban and rural, east and west, rich and poor, mixed and remixed. Six cities don’t represent America.

In New York alone, if you polled in Queens (the most diverse borough in the city) and Staten Island (the least), you would get very different results, and averaging them together would not yield a representative cross-section of racial experiences here. My CUNY undergraduates in the Bronx are much more vocal about race than my CUNY graduate students in Manhattan, who are (by a small margin) majority white. Why? Perhaps because of context: as majority minority students, they may feel a solidarity that empowers them to speak freely about race in the classroom. Perhaps because of geography: Unlike my grad students, many of whom hail from other states and countries, they’re largely from the same borough and feel comfortable talking with and about the ethnic groups they regularly encounter. Perhaps because of class: As lower- and middle-class students who aren’t as concerned about political correctness as middle- and upper-class white students, they tend to be open about their own biases—even accounting for what might not be said with a white professor leading the discussion.

As the browning of America progresses, I suspect these class discussions will become increasingly multifaceted, as will, I hope, conversations about identity across the nation. The MTV survey was right in concluding that race plays a big role in how millennials experience the world. But it was wrong in saying they don’t want to talk about it. After class, I headed back to my office to review my students’ hand-written narratives, and discovered the first one was prefaced with a question: “Is there any limit on how much I can write about this?”

Author Bio: Margot Mifflin is a professor of English at the City University of New York’s Lehman College and co-directs the Arts & Culture Reporting program at CUNY’s Graduate School of Journalism.