If your kids are like we were in high school, the book Good Dog, Bad Dog might be helpful. The main concept of the trainer who wrote the book is to work with the dog's natural tendencies to get the dog to do something right then praise the hell out of him.
I have never read the book but I saw the author of the early edition on TV, stole a couple of his ideas, and used them successful over the years to quickly teach dogs to heel, sit and stay.
You could start with praise even if your students haven't done much of that is praiseworthy. First, praise them for being in school and tell them that they've made a good decision. If they are noisy, praise their free spirits. If they are drugged into a stupor, praise them for being quiet and calm.