The best way to hold a class debate is usually to hold a class discussion. When people debate, they believe they are right and that the other people are wrong. When people discuss, both sides have different original beliefs, but are searching for the truth. The students should be the ones doing the searching and you as the teacher should be guiding them in the right direction to discover.
As an example let’s ask the question, “Is slavery wrong?” Notice that it is a question. We do not assume that slavery is or is not wrong, but want to know which it is. Have one person bring up one point first. Let’s say, “Slavery is good because it allows the owners to get a lot of work done for very little money.”
Now we ask the opposite side if they can refute the fact presented. If nobody can prove that slave owners didn’t get a lot of work done for little money, then the class should stop discussing that point. Maybe make a mark on the board to denote it.
With the first point over, the class should move to the next point. Ask if anybody has another point to raise. Let’s say the next one is, “Slavery is wrong because slaves aren’t free.” That is an important statement to discuss. Have it be discussed without letting it become an argument. Let’s assume that the point is supported.
After enough points are discussed, ask the class a value question. “We agree that slavery allows things to be made inexpensive, which is good, but that it takes away the freedom of the slaves, which is bad. So, which is more important: freedom for everybody or cheap goods for non-slaves?” This is the kind of question that will lead to the end of the discussion. Hopefully the students will now understand that they believe having freedom is more important than having money.
There are a number of things to keep in mind during this exercise. For one thing, keep it civil. Discussions turn into debates, arguments, and fights pretty quickly, especially with children. Next, keep it on point. Although there are bound to be tangents, make sure that they always lead to supporting or refuting a point. Also, keep the flow going. Taking too much time on one point may bog down the whole process. Excessive quiet time from students not participating will do the same thing.
Be inclusive. Get everybody to say at least one thing. If somebody is not talking, specifically ask the student what he or she thinks on a particular matter. The point is to get the students to think. If they can learn to consider multiple sides of an issue and do it without fighting, they will have a fantastic skill.