Although some schools do have a class, usually Anatomy and Physiology, where they try to weed out the people who can't handle the workload, many schools really do want their students to do well. Realize that even though your professors may be tough, they're only trying to prepare you well, not kill you.
Ask For Help
If you do find that you're having difficulty in dental school, ask for help. Most professors are more than willing to help students who are having problems in their class. Just be sure to ask sooner rather than later or you may be at a point where you can't improve your grades quickly enough.
Be Realistic
Remember that unless you really want to specialize, you don't need to be the top person in your class. In fact, all you really have to do is graduate, though it would be ideal to be in the top fifty percent of your class.
Study with Friends
When you do need to do a lot of studying, try creating study groups. This will combine studying with some fun, so you don't become burned out as quickly. Maybe you should go out to dinner or meet in the library with snacks and books so that you can study while having fun and food.
Take a Break
Although you may feel like you should study constantly, that will drive you and everyone around you crazy. Sometimes you just need to take a short break from working on stuff for your classes. Go out for dinner. Play XBox 360 - that's what all my friends in dental school do. Go for a run. Just think about something other than school for a little bit. I promise it will go a long way toward keeping you sane.
What to Remember
When you're stressed out in dental school, particularly during your first and second years, remember these things: