Take the Energy Star Home Challenge and make two improvements

Buildings are responsible for 40% of total energy use in the U.S., and almost half of our energy use at home is spent just heating the place up. How does your home energy use measure up? If you have five minutes to spare plus easy access to your recent utility bills, then you're ready to take the Energy Star Home Challenge.

There are countless ways to save at home, but it's important to know where you're starting from. After you complete the Challenge quiz, follow the links to discover hidden energy savings, from installing new air filters to taking advantage of rebates and tax credits for buying energy efficient appliances. Get inspired by real stories of success, then commit to making two improvements to your home energy usage.

Which changes are you going to make around the house?

Increase my Household Water Audit score by 5 points

Even though 70% of our earth is covered in water, less than one percent of it is available for our daily needs. As the Circle of Blue organization says it, "If all the world's water were to fit inside 100 glasses, the supply available to humanity would not fill three quarters of one glass." That's a small amount to share between 6.6 billion people!

How do you score on water savings? Spend two minutes taking the Family Water Audit to learn how your usage stacks up. If you make it to the top tier, you're already saving hundreds of gallons of water each month - not to mention the savings on your water bill. At the end of your audit, click on the "easy ways to save" links to explore more than 100 tips for conserving one of our most vital resources.

Despite my super score of 30 points, I know I'm a water hog when it comes to showering. Ripple Products inspired me with their fun line of shower timers, but I bet I can make my own using an extra timer from the game closet or the kitchen.

I'm committed to boosting my water audit score by 5 points, and I'm challenging you to beat me! Post your 'before' and 'after' scores below and show off your water-saving strategies in our Flickr photo pool.