How many beginning teachers struggle to create new lessons despite the fact that experienced teachers have already designed effective lessons for the same content? Shulman (1987) used the term "collective amnesia" to describe the failure of school leaders to design professional development that included the collection of its best practices. Technology, including the use of file sharing and school databases, may be the best solution to this problem. Few will deny that computers have affected how teachers do their jobs, but technology's effect on professional development is only just emerging, and school administrators are still learning how to use technology to improve student achievement. Although lesson plans and even online mentoring have proliferated on the Web, online support can't address the unique characteristics of school cultural norms and expectations. Currently, teachers at Beverly Hills (CA) High School can take advantage of a number of public and state-maintained Websites that provide almost unlimited resources for lesson planning. Although many sites provide general lesson plans for course content, several have begun to offer more personalized online mentoring and professional development. Content, support, and school-level norms--the three vital components--can all be addressed by school network file sharing which can respond to the dynamic interplay among all of the elements of effective professional development.