Specific due dates for the day you attend lab (Monday or Tuesday or...) are posted below. In general, Prelab assignments are due by 10 pm the night before an experiment and Postlab assignments are due by 5 pm the day before you next experiment. So you will always have two assignments due the day before your scheduled lab period; 5 pm is the postlab assignment due date from the previous week's experiment and 10 pm is the due date for the prelab assignment for the next day's experiment.