Use Calendars Effectively

I used two calendars in college, one to much better use than the other 

Google Calendar
Get a calendar set up in Google Calendar for just your classes.  Put your class schedule in it for the whole semester as soon as you get it set.  Once you get your syllabi, go through them all and put in EVERY MAJOR EVENT.  This means quizzes, exams, midterms, papers, finals, and anything else worth noting.  Update these things if they get moved.  You will never forget about an assignment ever again. 
Plan your days.  Your calendar shows you when you have class.  Put meetings, events, work, etc in their own colors.  This is a great way to find open spaces of time and minimize friction.
Your calendar on Google is available anywhere and can be shared with others.  Use it. 

Week By Week
I used a week by week for my first two years, then stopped carrying one.  Some people find them essential to planning out their weeks and putting in important dates.  Your important dates are in your Google Calendar.  The only real reason to use one of these is to write things down that the teacher assigns that aren't already in your Google Calendar.  When you get to a computer, you can then transfer these items to Google.  If you need a week by week for these shorter-term items or because you are apt to forget things before you get to a computer, by all means, use a week by week.  If not, don't.  Give it a try for a while and see if it's useful for you.

I'm sure there are other useful calendaring options out there (I went for a plain sheet of paper for "don't forget to add this to Google" stuff day-to-day), but these two are my recommendations.  At the very least, learn to use Google Calendar effectively.  It will be a lifesaver for prioritizing your work and optimizing you days.