Probably the best advice. Every day after ground school I didn't do ANYTHING related to class for at least 30-45mins after getting back to the hotel. You've been in a class room all day already and it pays to take some time to clear your head. You'll retain more if you're relaxed for studying at the hotel. And study with others in your class. You'll learn a lot from bouncing questions off each other. If you don't know something, chances are someone else has a slightly better grasp or a different way of explaing/understanding something that makes sense to you. Remember, most of your classmates were probably CFIs at some point and have experience explaing complex things. Just remember, everyone else is learning just like you are so don't expect them to be the end-all-be-all and don't rely on just their word, back it up with what you can find in your manuals or learn from instructors.