It also indicates that you are conscientious. Sit near the front of the room. You will have fewer distractions and you might be more willing to ask questions as the entire class can't turn around to watch when you speak. Look alert and appear interested in what is going on. Some Americans behave in a manner you may consider rude.
Classrooms tend to be informal.
Pay attention to what the professor or class is discussing. Be on time and don't talk to other students or read while the professor is lecturing. Write the professor's name, office location and phone number in a convenient place. If you do not understand something covered in class, ask to make an appointment with the professor. Try to make friends in class with someone with whom you can exchange phone numbers.