Abstract
The purpose of this chapter is to present a systematic observational research on the math teachers’ assessment practices in the classroom. This research is a specific phase of an international project (FAMT&L - Comenius Multilateral Project) and it is aimed to promote the use of formative assessment in teaching mathematics to students aged from 11 to 16. The observational study is carried out by a plan of systematic observations of teachers’ behaviour in the classroom with the help of video recording. Thanks to a specific tool of video analysis (a structured grid), developed using indications from international literature and experiences of teacher training in the five Partner countries involved (Italy, France, Holland, Switzerland and Cyprus), we managed to gather many different indicators on good and bad practices for the formative assessment of mathematics teachers. Furthermore, the analysed video will be used in in-service teacher training courses in order to promote a correct use of formative assessment and to improve achievements in learning mathematics.