US college classes may feel informal, but the rules are strict and written down.
The syllabus is the course plan the professor gives in the first week. It lists every assignment, the due dates, how the grade is calculated, the rules on late work and AI tools, and office hours. Treat it like a contract.
Read every syllabus in week one.
Put every due date in your phone calendar with a reminder 3 days before.
Note how much each part counts, for example: participation 10%, homework 30%, midterm 25%, final 35%.
Many professors grade participation: speaking in class, asking questions, joining group work and discussion boards.
It is normal to disagree politely with the professor or classmates: "I see it differently, because..."
You can ask questions in the middle of the lecture. Raise your hand.
Quiet students lose points. If speaking is hard, prepare one comment before each class.
Office hours are times each week when the professor or TA (teaching assistant, often a graduate student) waits in an office or video room for students. You do not need a special reason. Going early in the term builds a relationship that helps later, including for reference letters.
Each course gives credits (or "units"), often 3 per course. Credits usually match hours in class per week.
GPA (grade point average) uses a 4-point scale: A = 4, B = 3, C = 2, D = 1, F = 0. Plus and minus grades (A-, B+) change it a little.
Many programs require a minimum GPA, often 2.0 for undergraduates and 3.0 for graduate students, to stay in good standing.
Deadlines are firm. Late work often loses points every day or gets zero.
If you are sick or have a family emergency, email the professor before the deadline, not after. Ask: "Could I have an extension until Friday?"
Add/drop deadline: the date to change classes without a mark on your record. Withdrawal deadline: the last date to leave a class with a W grade. If you are on F-1 or J-1, talk to your international office before dropping anything.
Group projects are common. Agree on tasks and dates in the first meeting and write them down. If a member does nothing, tell the professor early.
Calling the professor only "Teacher". Use "Professor Lee" or "Dr. Lee" unless they ask for a first name.
Waiting until the final exam to ask for help.
Not reading the online class page (Canvas, Blackboard, Moodle) daily. Many announcements appear only there.