Consider making a lounge in your dorm room with the addition of a sofa, a futon or comfortable chairs. Add a few throw pillows to make the space more comfortable and a light blanket for the winter months. A storage ottoman can give you more space to hold your items, although you could also just keep various snacks in it, making them easy to reach from your loft "lounge".
If your dorm room doesn't have desk, or if that desk is relatively unsatisfactory, create an office nook for yourself. Include a desk and shelves to hold your textbooks, binders and computer. To maximize the usefulness of your space, install cork board or a dry erase board for notes and to aid you in your coursework, or a pegboard to better hold your supplies. Place a few lamps under the loft bed so that space is appropriate for studying.
A loft bed also can create storage space, perfect if your closet just doesn't cut it to hold all of your, and your roommate's, stuff. The easiest form of storage is to stack cubes or put in a few cheap shelving units. If you are making the loft bed yourself, you can simply build shelves into the design. If the problem is a lack of hanging clothing storage, consider placing a rod under your loft and installing a curtain in front of the space for a more uniform appearance.