This study aims to get ideas for improvement of in-service education for school teachers in Japan compared with the continuing professional development programme through mentoring in England. Recently the Japanese 'Lesson Study' has been popular as the effective method of the continuing professional development in USA and England. The good points of it were making cooperation and colleagueness among school teachers when they observed teaching and gave feedbacks each other within their schools. In England mentoring seemed to be important expertise for making cooperation and colleagueness between school teachers and was proposed as the continuing professional development programme. The results are summarized as following points. Currently in Japan, middle school teachers are expected to be good mentor for novice school teachers. Besides the reproduction of 'Lesson Study' as traditional Japanese school teachers culture is expected for making colleagueness among school teachers. So the continuing professional development for middle school teachers is seems to be crucial for realizing them. Middle school teachers have to get professional development of mentoring, coaching and co-coaching. The function of mentoring is assistance of professional development of novice teachers. Also the function of coaching and co-coaching is assistance of professional development of colleagues. It seems that in the area of curriculum and instruction study, researchers in teacher training providers have to assist school teachers for the continuing professional development concerning mentoring, coaching and co-coaching.