Hello. I am currently a senior mechanical engineering student. I've made a conscience effort to taking advantage of what the phone has to offer to me as a college student. I'm going to be honest, a lot of the functionality is built in already.
1. Onenote
I use Onenote so much. I use it on my laptop when I have to make a quick outline to gather my thoughts on something, or I use have the "new note" pinned on my phone so that I can quickly tap it and record something down. It syncs flawlessly between the phone, the desktop app, and on skydrive.com. Easily my #1 suggestion.
2. Skydrive
Skydrive is huge. All of my class folders reside within the desktop skydrive app. That means ALL of my class files are immediately pushed to the cloud and I am able to access them on any computer connected to the internet. This is huge for me. Say I'm working on a paper in my dorm. I can just hit save, go to work and open it up on the computer there. No need to bring my laptop, no need to upload to a flash drive or email it to myself. Also, Skydrive is an AMAZING collaborative tool. All my group projects, I make a Skydrive folder and share it with everyone in the group. With Office Web Apps, live multi-user editing, etc. it is a very powerful tool for working in groups.
3. Calendar
I make strong use of the calendar app. I have a class/work calendar which contain my class and work schedules. I have another more dynamic calendar to remind me about anything: group meetings, review sessions, professor office hours, etc. I put 15 min. alerts to make sure I never forget. Also, I organize all my hw assignments in the "tasks" pane within the calendar. Nothing more satisfying than crossing those off.
4. Groups
Whenever I have a group project, I put all members into a group. Emailing the entire group is just 2-3 taps away.
That's all I have for now...