Development of school-based in-service training under the Indonesian Mathematics and Science Teacher Education Project®

This article aims to investigate how to involve the entire school in in-service training (INSET) by means of a case study. It examines the cases in the Indonesian Mathematics and Science Teacher Education Project (IMSTEP). The results suggest that great emphasis be placed on various factors in order to develop INSET in the Indonesian context, particularly as a school-based training programme. First, the function of key persons is important. They are capable of initiating informal, yet genuine, sharing of experiences with their colleagues. Thus, the principal’s commitment is essential. Depending on the principal’s support and facilitation, the informal sharing of experiences can develop into a movement of professional development for teachers throughout the entire school. Furthermore, the collegial interests are also important. In the lesson study implemented under INSET, it is necessary for participants to cultivate the attitudes of mutual learning.