Ten secondary schools in a large state-wide education system initiated a virtual school network to address the lack of upper secondary school courses for university entry in smaller high schools. This article highlights the yearlong professional learning program designed to prepare a cohort of classroom teachers, who were novices to teaching online, for developing and teaching fully-online courses. In accordance with program goals, data include pre/post measures of teachers' capabilities and external course reviews using the iNACOL National Standards for Quality Online Teaching. Results show that teachers grew in all standards of their self-reported online teaching skills, and reviewers rated two-thirds of the 21 quality items as being Very Satisfactory and Satisfactory for a majority of the courses prior to teachers beginning to teach students. Findings indicate areas of emphasis for the ongoing work of the cohort's professional learning community.