Reduce what you use. Use things until they wear out, buy what you can second-hand and repurpose old things into something new.  When you buy new, you add to your carbon footprint. When you re-use instead, you cut and save cash. Instead of heading to a big-box retailer, furnish your room with great finds from

Craigslist, Gigoit, Freecycle, eBay or a second-hand store. Use recycled paper. Although it may cost slightly more, recycled paper saves trees, energy and water, produces less pollution, uses less harmful chemicals and requires less bleaching than virgin paper production. How much are you helping the earth by using recycled products? The Recycled Products Cooperative offers an online calculator so you can figure it out. There are a number of eco-conscious paper sources, ranging from big box stores like Office Depot, Office Max and Staples to the Recycled Products Cooperative, The Green Office, Green Earth Office Supply, Greenline Paper.
Know what you're buying. The general term "recycled" refers to both pre- and post-consumer waste. Pre-consumer material is of scrap material generated during the manufacturing process or created from unsold paper items like magazines or books that are returned (unsold) to the manufacturer. Post-consumer recycled means that a finished product has been purchased and used by an end-user and has then gone through the recycling process. The more post-consumer waste, the greener the product. For instance, the US Environmental Protection Agency requires federal agencies and federal contractors to look for at least 30% post-consumer content for most uncoated printing and writing papers, and 10% post-consumer content for most coated papers. You can learn more about paper choices at Conservatree, a nonprofit group that advocates for ecologically sustainable paper markets.
Look for third-party certification. Whether you're buying paper or cleaning products, approval from an organization like Green Seal or EcoLogo assures you a product lives up to its advertised green claims. Don't take green claims at face value.
Think about your purchases. Only buy what you need.
Buy used textbooks instead of new-and resell them, if possible, at the end of the semester. It's good for the environment, and just as good for your budget, since new textbooks cost around $500 each term. Check your campusbookstore for used book options, as well as sites like Bookrenter, which gives students the option to rent textbooks instead of buying them.
Change your light bulbs. Replace standard incandescent bulbs with compact fluorescent light bulbs (CFLs), which use about 75 percent less energy and last up to 10 times longer. They cost more initially, but you'll save money in the long run.
Give up bottled water. Between 2002 and 2007, world consumption of bottled water jumped by 7.6 per cent per year, from 130.95 billion litres to 188.8 billion litres, according to the Beverage Marketing Corporation. The United States consumes the most bottled water on the planet (33.4 billion litres). Buy a reusable water bottle and fill it from the tap instead. If you don't like the taste of the tap water in your dorm, buy a Brita pitcher to remove taste-killing impurities-and use this coupon to get $5 off the purchase.

Chose plastic over paper. Buy a bowls, plates, cups and utensils that you can wash and reuse. You'll minimize the trash you create with paper products and save money because you won't have to keep restocking paper goods.
Use your feet. Walk or a bike from your dorm to your classes, or, if necessary, use campus shuttles. Take the stairs instead of the elevator when possible: Walking up or down as many as six flights of stairs is usually faster than waiting and riding. In addition to saving energy, you burn calories.
Reduce appliance dependence. Use your dorm's community kitchen to save energy. If you can't bear the thought of forgoing a fridge or microwave in your room, then make sure you choose ones that are Energy Star compliant. If you're looking for a combination microwave-refrigerator unit, MicroFridge units are an energy efficient option. You can search for energy saving compact refrigerators on the Energy Star site.
Compute your energy use. Buy a notebook computer rather than a desktop because they generally use around 50 percent less energy. Make sure the unit you select carries the Energy Star rating. And once you have it, activate the power management features. It will cut the electricity used in half, saving $25 to $75 per computer annually. You can estimate your savings with this online calculator .
Sleep tight. Look for sheets made from organic cotton, which grown using methods and materials that have a low impact on the environment, or bamboo, one of the fastest growing plants on the planet.
Color your world green. Stock up on towels made from organic cotton or hemp, which is generally grown with few, if any, pesticides. Buy a rug made from a natural material, such as bamboo, coir, hemp, jute, mountain grass, sisal, seagrass, paper or wool. Look for a shower curtain made with PEVA, which contains no chlorine-the source of dioxin-or phthalates instead of potentially problematic PVC vinyl. Decorate judiciously: resist the urge to clutter your room with knick-knacks you'll probably throw away by the end of the school year.
At the end of the year, pack up your stuff in recycled boxes and take them to a storage facility near your school. It will be more energy efficient than dragging them all home and back again when school resumes.