Many of the topics addressed in this textbook are unpleasant or controversial. That's because much of history is, unfortunately, unpleasant and controversial. But you can't avoid those issues in your classroom -- not if you're going to teach history responsibly.

You can't, for example, teach the history of the American South without teaching about slavery, or about Jim Crow. These topics make many students -- and teachers -- uncomfortable. They should make people uncomfortable. Many students and teachers have strong opinions about them -- and, again, they should. But without an understanding of slavery and segregation, the civil rights movement makes no sense.

Controversial issues are also key to teaching critical thinking. Research shows that learning and discussing controversial issues in school helps students become more informed and more active citizens, making them more likely to vote in later life, support basic democratic values, have confidence in their ability to influence public policy, do charitable work, and take an interest in the welfare of their community.

While we might avoid controversial issues, engaging students in these discussions is a critical exercise that plays an important role in their development as thinkers. How, then, can you have a thoughtful, productive, civil discussion about topics like race, religion, slavery, poverty, and war? Here are some pointers.

Establish ground rules at the beginning of the year.

Set ground rules for civil discussion before problems arise. You can do this cooperatively, taking students' input: Ask them how they would, and would not, like their peers to respond to their opinions and ideas. The rules agreed on should prohibit inflammatory language, name-calling, personal attacks, and sarcasm, but they should also state clearly what discussion is for -- analysis, understanding, and thoughtful evaluation. They should also promote turn-taking and ensure that everyone has the opportunity (and is encouraged) to participate.

Encourage attentive listening.

Some teachers require a student to restate another student's opinion in a way that is satisfactory to that student before he or she may state an opposing opinion. (This also forces students on both sides to communicate their opinions clearly.)

Focus on issues, not opinions.

Instead of asking what students think about an issue -- let alone how they feel about it -- ask them how different types of people might respond to that issue. Ask why the people you're studying said or did certain things, and what other people might have said or done in response, and why. Every issue has multiple perspectives, and this strategy requires students to consider them.

The digital textbook is designed to encourage considering multiple perspectives -- by, for example, placing an interview with a former slave next to the diary of a slaveholder. You may find it useful to pair sources that, even if they don't directly contradict each other, offer different perspectives or were produced by people who would disagree on a given issue.

Prepare for feelings, but focus on thoughts.

Sometimes, students will want to share personal stories and feelings. Provide space for this. Be prepared for students to be emotional, and try to support and comfort them. You may also want or need to be available to students outside of class if the issues provoke particularly strong feelings.

At the same time, the point of studying history is to understand the experiences of people who are not like ourselves. When students state broader opinions, require them to support those opinions with evidence, rather than speculating or relying solely on personal experience. However strong our feelings are, we have to learn to set them aside or move beyond them before real learning can take place.

Use other people's words to guide discussions.

Using secondary sources to initiate discussions of controversial issues allows students to see how others have talked about these issues. Statements by historians or other scholars-- even a single quoted sentence-- to which students can respond may help get discussions started when students are hesitant to voice an opinion. You can also use some primary sources for that purpose: Ask students to respond to a statement made by a historical figure based on what they know about the time period.

Avoid binaries.

Not only does every issue have more than one side, practically every issue has more than two. There were blacks who owned slaves and whites who opposed slavery but hated blacks; there were slaveholders who went to church on Sunday and had religious justification for the horrific punishments they dished out, and there were slaveholders who taught their slaves to read and fantasized about freeing them. The Revolution had Patriots and Loyalists, but also people who wanted the whole thing to go away, and the Patriots sniped at each other about how patriotic they were. Use a variety of primary sources to get students talking about gradations of opinion rather than either/or.

Encourage students to write before speaking.

Journaling or other informal writing gives students a chance to sort through their feelings and organize their thoughts before jumping into a discussion. Sometimes the most heatedly expressed opinions are the ones we realize too late we can't really support.

If the discussion gets overheated...

What if, despite your best efforts, things get out of hand? Try these strategies:

• Call a time out to give students a chance to calm down.
• Describe what's happening: "This discussion is getting uncomfortably hot" or "We've stopped listening to one another."
• Refer students to the class ground rules.
• Rephrase students' points of view in language that is drier and less emotional.
• Encourage students to analyze the argument. You might say, "This is the kind of topic that starts flame wars on the internet. Let's try to figure out why it arouses such passion."
• Ask students to reflect on what happened in class and to describe the disagreement.
• Have students take a few minutes to write out their opinions and feelings. This gives them a chance to express themselves; it also gives you a few minutes to figure out what to do next.
• Finally, remind students that we can't change history, and we can't impose our own modern values on people who lived decades or centuries ago. People in the past thought about and reacted to events and issues in ways that reflected their own contexts and experiences, which are very different from ours. Bringing the discussion back to the historical context may alleviate some of the tension.