I am a philosophy professor and I have my Ethics students engage in something like a parliamentary/panel debate. Students do Constructives and Cross-Examinations (but no Rebuttals). They also submit to an audience Cross-Ex (more or less like they do on Intelligence Squared).

Anyway, I'm experimenting with making the debates a more central aspect of the course, so I'd like to spend a bit more in-class and out-of-class time talking about and working on debate skills. My students are, in general, totally unexperienced with debate. I teach at a CC where there is no debate team, and maybe 1 in 50 of my students have ever been on a HS debate team or done a formal debate before.

Can any coaches or debaters recommend any resources (readings, tools, exercises) which they think would be helpful for such students? I'm interested especially in things which might aid in teaching students how to invent constructives and how to see spaces for questions.

For reference, I've taught argumentation before, but never Debate. I frequently teach my classes Toulmin instead of formal logic for purposes of analysis.