This study presents a case study about using a blog as a tool supporting and reflecting teachers practice concerning the development of technological, pedagogical, and content knowledge (TPACK) of teacher in-service course participants. The participating teachers were studying the contents of Finnish crafts for one and a half years between the August 2012 and December 2013. The challenge related to the in-service education is the paucity and shortness of intensity days during the educational periods. The personal blogs served a media for the course participants to support, reflect, and share their work and learning. According to the study, using educational blogging becomes more meaningful and more target-orientated during habituation of using the blog. Blogging proved to be a useful method for describing craft processes, monitoring the processes of others, and generating ideas for craft products.