I am professor of Communication Arts and Sciences at Penn State. I have 20+ years of experience teaching rhetoric and argumentation. In evaluating your debate performance, I am looking for the following:
are you able to formulate clear contentions in response to the resolution?
are you able to substantiate your claims with relevant and credible evidence?
do your arguments show good reasoning (are your warrants sound? do you avoid fallacious reasoning?)
are your questions during cross-examination helpful to your case rather than random? are you able to use the results of cross-examination to your advantage later in the debate?
are you able to respond effectively to all the contentions and rebuttals of the other side?
are you able to structure your contentions in a way that supports your proposition?
are you clear in your statement of claims and support?
do you use clear signposting and transitions?
in rebuttals, do you clearly introduce the opponent's claims and how you refute them?
are you able to summarize your own and your opponent's cases side by side when you argue the relative strength of your case?
3. Communication and professionalism:
do you communicate in clear, uncluttered sentences?
are you speaking at an appropriate rate and volume to be clearly understood?
do you articulate/pronounce your words clearly?
are you polite and respectful your the opponents?