The present study examined continuity of learning between face-to-face and online environments in a "blended" professional development program designed for 16 physics teachers. The program had nine face-to-face meetings as well as continuous online exchanges between them through a website. The program focused on "knowledge integration" (KI) innovative activities in physics classes using an "evidence-based" approach: The teachers implemented the activities, collected and analyzed data about their practice and their students' learning, and reflected on the evidence with their peers. Five reflective tools were used to promote continuity: "Your Comments", "Hot Polls", "Smashing Sentences", "Hot Reports", and "Mini Research". Continuity was assessed with regard to the ideas discussed by the teachers and the reasoning patterns that they employed. Analysis of the online exchanges in relation to teachers' face-to-face discourse revealed that the teachers discussed the same ideas (KI, evidence and learner-centered pedagogies), employed the same reasoning patterns (e.g., forming generalizations), and extended ideas in re-visitation. The online and face-to-face environments played different and complementary roles in the teachers' learning. This study shows that appropriate use of an online environment in a blended program can lead to a continuous course of learning and can transform a "9 once-a-month-meetings" workshop into a "9-month" workshop.