Professional Development of Maths Teachers

For a long time, 20 to 30 years, the professional development of teachers has adhered to the principle of beliefs and practices. What a teacher believes about teaching and mathematics is what they do in practice. This has been a common model for the design of professional development programmes and materials. However the link between beliefs and practices is not easy to determine, it is not obvious and not clear. Furthermore evaluations of professional development programmes do not demonstrate clear evidence of effectiveness of professional development.