Unplug your laptop, turn down the heat a degree or two and swap out those old electricity-sucking CFL light bulbs. It’s that time of year again — the Classroom Energy Diet Challenge is on!

Canadian Geographic Education, in partnership with Shell Canada, just launched the third annual school-wide competition, aimed at increasing students’ energy awareness and challenging them to trim kilowatts for great prizes. This year, Canadian classes, from Vancouver to Gjoa Haven, Nunavut to St. John’s, N.L., have the opportunity to win 40 prizes totaling $40,000, including $10,000 towards a school project that will reduce their school’s carbon footprint.

But prizes aren’t everything. Here’s a look at how much energy students saved during last year’s Classroom Energy Diet Challenge.

• A total of 3,715 people pledged to reduce their energy use
• 473.5 L of water saved
• 156 hours of energy saved
• 960 energy-saving challenges completed classrooms across Canada

Registration is open now until January 19, 2014. Refer a friend and click here to enter for a chance to win a $100 Visa Gift Card.

Take a peek at what Christine Todd, vice-principal at Duncan Cran Elementary in Fort St. John, B.C., has to say about the Classroom Energy Diet Challenge.