This study explored (1) pedagogical strategies in Educational Coding and Robotics (ECR) learning which can develop computational thinking of students and (2) the degree of teacher centrality in the ECR classroom. In addition, we investigated (3) the added value of the Small Private Online Course (SPOC) to teacher professional development (TPD). We analyzed reflections of 80 in-service teachers on TPD through the SPOC (1,091 statements) and conducted semi-structured interviews with 13 of them one year after completing the course and teaching ECR in the classroom (328 statements). The most prominent strategies immediately after the TPD were "constructing learning experiences," "tinkering & debugging," and "interdisciplinary learning," while one year later, "experiential learning" and "collaborative learning" were more common. Regarding the degree of teacher centrality, a year after teaching ECR curriculum the teachers had a significantly higher percentage of statements reflecting their role as a "guide-on-the-side" and as "a partner" of students in the learning process. Regarding the contribution of the SPOC for TPD, teacher statements revealed significantly more benefits than challenges in both points of time. Interestingly, the same categories emerged bottom-up as benefits and challenges: a variety of "control dimensions," "independent learning," "learning and knowledge management" and "collaboration." Implications for educational theory and ECR practice are discussed.