On August 9, 2014, the police officer Darren Wilson shot and killed Michael Brown on the streets of Ferguson, Missouri. Wilson is white; Brown was black. He was also unarmed. Within a few days, Ferguson was engulfed in riots. In dozens of other American cities, thousands of protesters took to the streets to condemn racism and police brutality.

The cover of "The Case for Contention" is yellow with the drawing of a desk and chair.
University of Chicago Press

Some schools in the Ferguson area delayed their scheduled opening to allow work crews to clean up the post-riot debris and to make sure that students could be transported safely. When they finally opened their doors, the schools had to decide how—and whether—to address the Brown shooting and its aftermath. Across America, demonstrators chanted that “Black Lives Matter.” How would Ferguson-area teachers make the controversy matter, and to what end?

Not surprisingly, their approaches varied. In University City, a suburb bordering St. Louis, one teacher led students in a “free-ranging discussion” of race, criminal justice, and inequality. “They were able to deconstruct the issues in terms of looking at things like poverty, education, the militarization of the police department, and the perception around the country and the world that St. Louis was in turmoil,” the teacher proudly recalled. But across the Mississippi River in Edwardsville, Illinois, school officials instructed teachers to “change the subject” whenever Ferguson arose in class. And in Riverview Gardens, the district where Michael Brown was killed, officials told teachers to talk about the issue only when students raised it. If students became “emotional about the situation,” teachers were advised to refer them to school counselors and social workers.

Edwardsville is a majority-white district, and Riverview Gardens is majority-black. But in both places, the reason for restricting discussion was the same: a fear that teachers were inserting their own biases—and inflaming an already-volatile situation. The major focus of concern remained the psychological well-being of the students, not their intellectual or political growth. Indeed, for many educators in the region, “politics” was exactly what schools needed to avoid. It conjured visions of emotionally fragile students, rising up in anger and possibly violence over the Ferguson situation. But perhaps this is the wrong approach, and public schools ought to address controversial issues that they too often avoid. The Ferguson episode merited the attention of schools: The issue was the focus of disagreement among experts and of broad public interest and concern.

On the airwaves and op-ed pages, scholars debated the origins of the Ferguson unrest and its larger implications for American race relations and criminal justice. And across the country, in person and in social media, millions of citizens engaged in lengthy and often impassioned conversations about the situation. Alas, it was precisely the volume and the vehemence of public discussion that led many educators to eschew it in public schools. And that, too, has been a recurring theme in the history of American education. As the Ferguson examples illustrate, people simply do not trust teachers to engage students on controversial issues in a knowledgeable and sensitive manner. Nor are teachers given the space to conduct these discussions in the school timetable, which is increasingly dominated by preparation for high-stakes standardized tests. As one report from Riverside Gardens confirmed, “there are too few educational hours available” to address events like Ferguson and to ready students for tests in reading and math, especially in underserved schools where many pupils lack proficiency in these areas. Indeed, as research has repeatedly confirmed, poorer students are even less likely than other youth to examine controversial issues in their schools.

Schools teach many things. For the most part, though, they have not taught students how to engage in reasoned, informed debates across society’s myriad differences. Simply put, the rhetorical commitment to “teaching controversial issues” in American schools has not been reflected in day-to-day classroom practices. Thanks to poor preparation, some teachers have not acquired the background knowledge or the pedagogical skills—or both—to lead in-depth discussions of hot-button political questions. Most of all, though, teachers have often lacked the professional autonomy and freedom to do so. That is particularly the case during wartime, when schools have sharply curtailed discussions of America’s military conduct. But throughout America’s history—and into the present—teachers have faced formal and informal restrictions on political discussions of every kind. Rising education levels have probably increased this pressure, emboldening citizen challengers who formerly might have deferred to teachers’ superior knowledge and credentials. “The high-school teacher has in fact lost relative status in recent years as more and more parents are themselves high-school graduates,” the eminent sociologist David Riesman observed in 1958. “And while the kindergarten teacher gains admiration because she can control several dozen preliterates whose mothers cannot always manage even one, the high-school social-studies teacher has a harder time being one-up on American-born parents who can claim to know as much as she does.”

That is even truer today, as more and more parents have obtained college and graduate degrees. But secondary-school teachers—and, in particular, those who instruct social studies—still face uniquely sharp constraints, for reasons that Riesman spelled out over half a century ago: “High-school teachers can become labeled by their students as ‘controversial’ as soon as any discussion … gets all heated or comes close to home,” Riesman wrote. And the threat was greatest in social studies, which “both draws on what is in the papers and risks getting into them.” In many communities, that was simply too big a risk for social-studies teachers to take. So most of them taught what Riesman called “social slops”—a litany of clichés and pieties—and avoided anything controversial that could only get them in trouble with one part of the public or another. “They fear that to utilize ‘controversial issues’ in education exposes them to criticism,” wrote future Vice President Hubert Humphrey, a few years earlier. “This has produced a nagging insecurity which in turn has forced many teachers to abandon valid educational techniques.”

To be sure, many other school subjects—not just social studies—involve potentially controversial issues. Teachers across the curriculum have struggled to balance their duty to address these issues with the inevitable pressures to eschew them. In the 1920s and 1930s, for example, American high-school science teachers emphasized physics and chemistry but down-played biology. The reason was obvious: Unlike the other major sciences, one observer wrote, biology threatened to “acquaint high-school boys and girls with the theory of evolution.”

Citizen complaints have also restricted the forays of English teachers into controversial questions. Sometimes, teachers have been barred from assigning The Catcher in the Rye, The Adventures of Huckleberry Finn, or the other so-called “banned books” that raise hackles at school-board meetings across the country. Even when such works have been allowed, however, teachers often experienced sharp limits on discussing delicate themes in the texts—especially those surrounding sex. Finally, school-mandated sex education has also been a constant target of community objections. It has typically devolved to health- or physical-education teachers, who have often stripped their lessons of anything too explicit—or too controversial—for fear of alienating one parental constituency or another.

Laws, school officials, and community opinion have all conspired to prevent or discourage American teachers from discussing controversial issues in their classrooms. This is not to say teachers have always avoided such issues: In 1953, at the height of the Cold War, a survey of social-studies teachers in Ohio revealed they were leading classroom discussions about whether President Harry Truman should have seized steel mills, whether Truman should have fired General Douglas MacArthur, and whether—as MacArthur wished—the United States should have used an atomic bomb in the Korean War. That same year, in another survey, New York City teachers reported holding debates on whether “Red” China should have a seat in the United Nations, whether Communists should be allowed to teach in public schools, whether Julius and Ethel Rosenberg should have received the death penalty for passing atomic secrets to the Soviet Union, and whether Senator Joseph McCarthy was “a menace to or savior of American democracy.”

After several teachers were dismissed for their own Communist affiliations, some admitted they were afraid to discuss anything controversial in their classes. But the survey seemed to show their concerns were misplaced, or at least exaggerated. “Let the teachers who do have these fears take heart,” the survey’s author wrote. “The very subjects which they say they are afraid to teach are being taught by many of their colleagues in adjoining classrooms and neighboring schools. Such teachers are imposing an unnecessary censorship on themselves.”

Into the present, some evidence indeed suggests teachers overestimate the constraints on addressing controversial issues in their classrooms. Novice teachers, especially, express surprise when they hear about veteran instructors who openly discuss divisive public questions with their students. “You let them talk about what?!” teachers in a recent study asked a colleague when they heard about her lessons. “You let them express what opinion?” In many ways, these remarks speak to the new teachers’ weak preparation for one of their central civic roles: to explore controversial issues with future citizens. It’s also a reminder that this kind of instruction continues to occur, despite the paucity of professional training for the task and—particularly in recent years—the shrinking legal protections for it.

When the United States attacked Iraq in 1991, students at a Pittsburgh high school walked out to protest their school’s refusal to address the issue. But 12 years later, when America invaded Iraq again, a high school in suburban New York sponsored a full-day discussion of it. At an all-student assembly in the gymnasium, five students and two social-studies teachers presented arguments for and against the war; then the students dispersed to their respective classrooms to continue the conversation. America’s classrooms are rife with opportunities for growth through controversial topics. The question is whether teachers will be empowered to address them.

This article has been adapted from Jonathan Zimmerman and Emily Robertson's book, The Case for Contention: Teaching Controversial Issues in American Schools.