Increasingly, teacher leadership is being recognized as an essential ingredient in education reforms; however, few teachers consider themselves leaders. Becoming a leader is not just acquiring knowledge and skills for leadership, but developing a new "professional identity." As teachers become leaders, however, this identity might put them at risk with dominant school culture where norms of egalitarianism, isolation, and seniority persist. Luehmann emphasizes the value in offering safe spaces in which teachers can take risks as they "try on" new identities. We utilized an online environment to support ninth-grade science teachers in the development of common perspectives, commitments, and visions for teacher leadership as they implemented a new freshman physics curriculum. Our findings illustrate the potential benefits of blogging in terms of providing identity resources and opportunities for identity work. Specifically, by participating in "pedagogical transactions," "social interactions," and "intellectual deliberations" via blogs, teachers were supported in their efforts to be leaders in their classrooms, schools, and districts.