Let your teen be the one to come up with his daily routine. They are more apt to stick with it this way. Set up a consequence if they are unable to stick to the routine, beforehand. An example of what I use is if the time is 7:00 pm, and they can't get to the table until 7:05, then no TV, (stereo, going out with friends, ...pick one), for the rest of the night. Use an Action Plan at the beginning of September to help keep up the schedule throughout the school year.

Here is an example from last year:
I had a teen bring home a note that said he didn't get a project done, and he needed it done or he would fail the class. Instead of picking up the responsibility for the project, I handed it right back to my teen. I didn't ground him, I didn't get caught up in that sinking feeling I was having, I took a deep breath and said, 'Geez, I think I would get it done.' Then I put a piece of imaginary duct tape over my mouth, and held it shut. He got it done, and passed the class. If I would have told him to get the work out now, and we'll do it together, the next time it would happen again. And he would have learned nothing.

I am in no way implying that I didn't worry about it, I never said that handing over this responsibility is an easy thing to do. But, there are worse things in life than bad grades, and a young adult that doesn't know how to take responsibility for themselves is one of them. So teach your teen now, while you can.