In this article, the author features "the sidewalk project" in Littleton High School. The sidewalk project is a collaboration of more than 40 high school physics students, 10 local mentors, and a few regional and national organizations who worked together to invent a way to heat a sidewalk with an alternative energy source. The project, which began in the spring of 2002, provides a vehicle for teaching applied physics concepts such as energy and its many forms, thermodynamics, and electromagnetism. The project also offers authentic ways for students to engage in meaningful experimental and engineering design and to practice their scientific writing skills. (Contains 1 figure.)