I generally start the day with a whey protein shake mixed with some low fat milk, yogurt, a banana, and some sort of grain, like an english muffin or bowl of oatmeal/cheerios. On days I have more time in the morning, I'll fry a few eggs and eat the whites.
Lunch generally consists of either PB and J or some bagged tuna i spread over bread, as well as some raisins/peanuts, granola bar, and a small bag of chips (its important to endulge in a little junk food to keep you sane in my opinion).
I'll usually come home, and have my dinner defrosting in the fridge. Its usually chicken, fish (both in the oven) or steak (on the grill). I cook up rice in a rice cooker (those are amazing and a life saver! check them out!) or boil pasta. I'll heat up some frozen broccoli in the microwave or on the stove, bake up some texas toast, and get down for dinner.
I work out often so I'm usually hungry around 9 PM. I'll make a sandwich, cook up something frozen like a "healthier" TV dinner or frozen pizza, maybe some chips and salsa.
Before I go to bed its another protein shake and some fruit.
Overall its a pretty healthy diet mixed in with some devils delights. Its important that your getting the right nutrients, and by that I mean buying whole grain products and not processed/white flour. Also, get plenty of seafood and other items containing polyunsaturated fatty acids/omega 3s and 6s. These are the ULTIMATE brain food bar none. Stick with frozen vegetables over canned and even fresh. Their frozen at farm and thus the nutrients are locked in, and you dont have to worry about them going bad, being a student. Bananas are very nutritious and they last about a week, and apples last a long time in the fridge. Raisins, ditto without refrigeration.
Its very easy to put together a healthy diet routine with a little thought. But remember to get yourself your unhealthy fix every now and than. Everything in moderation is ok.