Having a mattress pad is essential in college. Actually, it's my number #1 product purchased off my website and I couldn't agree more.
This mattress pad is what I used my first two years of college and then passed down to my sister when she went to college. It is GOOD and truthfully, made my bed even more comfy than my mattress at home.
I recommend getting 4" or more and make sure you get the twin XL size.
I have a whole post on me talking about this mattress topper...You can read it here: This Is The Absolute Best Twin XL Mattress Topper For Your Dorm Room