Yes, but a more important function of debate in school is to expose people to new ideas and to question assumptions. Unfortunately, debates are often structured in a way that forces students to accept some ideas and prevents them from expressing others, which is a problem.

For example, whether you argue to raise or lower the minimum wage, either way you are still implicitly accepting the wage system. By framing the debate in this way, the teachers prevent students who oppose the wage system from having an opportunity to express their views.

Another example - as Noam Chomsky wrote about in "Manufacturing Consent", after the Vietnam War, the New York Times discussed many different theories for why the US didn't "win" the war. But it never considered the obvious - that the war itself was a mistake, and the US was wrong to be there in the first place. Framing the debate in this way is a way of silencing the opposition, by presenting two "sides" that are actually both on the same side and only disagree about trivial details.

If you opposed the Vietnam war, then it would be against your interests to follow the rules of a "debate" about how to win the war. The correct course of action in this scenario is to take the opportunity to argue for what you believe and to undermine the debate itself, even if it results in you "losing" the debate.