This study investigated how a school-based professional development programme, designed by the Headteacher and staff of a Kenyan primary school, and delivered by a Teacher Education in Sub-Saharan Africa (TESSA) team, supported teacher learning and growth. The TESSA team observed teaching in the classroom before the implementation of the school-based teacher professional programme. This was followed by the training of the teachers in the school. The TESSA team did an evaluation of the school-based training programme through classroom observation, an interview schedule and a teacher questionnaire. The evaluations were done three months and one year, respectively, after the school-based training. The findings indicate that teachers experienced professional growth through collaborative learning with colleagues, used a greater range of approaches and learned to self-reflect on their classes with more use of active learning. Teachers made productive use of textbooks as well as accessing and using TESSA OER in teaching.