<p>You never know if a few spots will remain open (especially the 8am class) or if they will add a few spots if you contact the professor. Sometimes a new section opens up. Even if the classes fill up, keep watching the classes every day during the registration window and sometimes a spot will open up briefly and you have to grab it up. Also, there is a chance that you can get into the class during the first few days of drop/add.</p>