I've been to a few defensive driving courses in my time. They can be worthwhile if you want them to be. It also depends on the instructor. The coolest I went to was done by a cool woman who likes riding motorcycles. Once I went to one in California, where I used to live, and the instructor apparently didn't want to be there either. So he just had everyone sign in, then sent us home. If one of the students had wanted to turn him in, I'm sure he would have been in trouble
If a class can keep you from getting a ticket on your driving record, its definitely worth it.