Finally, please understand that your success or lack thereof is your responsibility. Every one of the items above is under your control. You should not expect any special consideration from your teacher if you have missed classes, not done homework, or not put in a sufficient amount of time. On the other hand, we understand that there are situations in which students are forced to miss classes, sometimes for an extended period of time, through no fault of their own. In these cases, you should try to stay in touch with your teacher through e-mail or some other means.
Most teachers have web pages or forums on which they post assignments.
There is no question that such absences will make your academic life more difficult, but, especially if you have demonstrated a sense of responsibility, your teacher will try to help you through these periods.