Late homework must be sent to the instructor who will give detailed feedback to the student, but will not give any credit. Homeworks should be graded in a timely and fair fashion. Graded homeworks should be returned by email to the students within at most one week from the deadline. Above all remember that homeworks are a wonderful learning opportunity for students. Do all that you can to make sure that learning is taking place.
Grades are of secondary importance.
When students come with questions, be kind and helpful. Outside of the scheduled hours use your judgement on how much to make yourself available to students. But in all cases, be very polite and explicit about what you can and cannot do. Check your email frequently and answer questions in a timely fashion. Replies should be given within 24 hours, but, if possible, within the same day they were asked.