9.
Turn off lights and appliances when no one is in the room
Lighting accounts for nearly 50% of the electric bill in most schools. If you are the last to leave your dorm room, classroom or lab flip the switch and turn out the lights. For incandescent lights the energy savings are immediate. For fluorescents there is some energy cost to switching the light back on. However, if the room is empty for more than 15 minutes, then it will usually save energy to turn the lights off. Similarly, leaving a desk-top computer running the whole year will cost you more than 1,000 kW which is about a full month’s energy use for a 4 person family.
http://www.eere.energy.gov/consumer/your_home/lighting_daylighting/index.cfm/mytopic=12280