The One Thing Challenge is an annual competition between residence hall students at the UW and Washington State University (WSU) to win their school the title of Greenest Campus. The campus with the most participants will celebrate with bragging rights and the ceremonial awarding of the One Thing Tapestry (made of recycled T-shirts).
The One Thing Challenge is a personal commitment to change one thing in your normal routine in order to be more environmentally friendly. By committing to One Thing, you're not radically changing your life. However, that One Thing can lead to other One Things, and you'll find that there are many things you can do to save energy, water and fuel to reduce your impact on the environment.