While keeping a notebook for your daily assignments is important, calendars help visualize a schedule. Especially if you're busy with extracurricular activities like music or dance lessons or sports practice, calendars are an easy way to stay organized and remember which days are for which activities. If you write down when things are due, it helps you visualize how long you have to study for tests and write papers, and you can pencil in a special day-by-day work schedule, which helps with time management. Some Web sites offer online calendars, like MSN, Google and Yahoo, where you can keep track of events from any computer. This way, you can check in whether you're at home or at school.