What do teachers learn about their teaching when their students engage in curriculum-based online learning projects? This qualitative study explores beliefs about on-the-job, profession-related learning - or "authentic professional development" - among eight teachers whose students participated in educational projects hosted by five well-established programs: The Electronic Emissary, iEARN, KidLink, ThinkQuest, and ThinkQuest Jr. Telecomputing alone does not change teachers' teaching styles. Instead, teachers who are innovative, inquiry based, and student centered may find telecomputing to be a useful tool for helping their students become more confident, self-directed learners.