A list also has the advantage of allowing you to see all of your obligations on the page, which reduces the stress of being over-obligated. Somehow, when you can reduce the things that need to be done to a short piece of paper, it doesn't seem quite so intimidating. I begin every day with a list of the things I need and want to accomplish that day. I also have a white board which I use to keep track of tasks that last longer than one day. That way, I can see at a glance what assignments, meetings and classes are coming up.
Lists also offer opportunities to celebrate.
It feels REAL good to cross off an item. And when my white board starts to look empty, it's a REAL nice feeling. This decision is up to you. Some people work very well when they give themselves, say, an hour to do their math homework, or 45 minutes to clean the kitchen. If this works for you, then by all means, schedule out the amount of time you think you will need to spend on each task.