Remember to practice what you've learned during the week between classes. Fifteen minutes a night should do it. Practicing outside, especially in a park where there are distractions your pup will learn to ignore, is a great idea--and a great way to meet fellow dog lovers.
If you keep training sessions short, especially for young puppies, stay enthusiastic, and never lose your temper, before long you'll have a dog with handsome manners who will be welcome just about anywhere. And best of all, once your obedience course is over you can sign up for another one.