This web site, created by the National Center for Atmospheric Research (NCAR) in collaboration with teachers, contains teacher-crafted classroom activities designed to enhance middle schoolers’ skills in science and math. “Cycles of the Earth and Atmosphere” builds the excitement of scientific discovery into the curriculum, along with the basic concepts middle school students are expected to master. Topics include climate, the greenhouse effect, global climate change, the ozone, and the atmosphere as a whole. Each section provides background materials and several classroom activities that let students become hands-on participants in the scientific discovery process. One animation on the site demonstrates how manufactured chemical compounds known as chlorofluorocarbons (CFCs) destroy the earth’s protective ozone shield: CFC molecules rise into the stratosphere, where ultraviolet radiation breaks them apart, releasing chlorine, which then attacks and destroys an ozone molecule by knocking off one of its oxygen atoms. The site’s content grew out of a series of summer workshops, in which 40 teachers worked with more than 60 scientists from NCAR and its parent organization, the University Corporation for Atmospheric Research. “The site is designed to be a work horse for teachers,” says project director Sandra Henderson. According to Henderson, everything on the site is aligned with the national standards for science and math education, which form the framework upon which most state and district standards are built. The site is a great resource for earth science teachers who want to use the web to bring unique learning opportunities into their classrooms.