Study to know and understand.

While grades are important, as an undergraduate it's important to study not only to get good grades, but also to know and understand the material. When you're an intern the people you work with will throw tons of questions at you, including ones you could never have thought you would be asked. This is where it's so important to understand all of the aspects of your DPD classes. A coworker might ask you at lunch if he should be eating carbs after a workout, in addition to the protein supplement he already takes. And a community member attending a class you are teaching might ask what exactly an amino acid is, and how it's different from the acid in fruits. And the better you know your stuff, the more easily you'll be able to answer their questions.