The study presented in this paper discusses the results of a three-year project conducted by INDIRE, the National Institute for Documentation, Innovation, and Educational Research, in collaboration with four Italian comprehensive schools. These schools worked within a vertical continuity framework (from early childhood to primary and lower secondary education) to introduce the Making Learning and Thinking Visible approach into their daily teaching practices.

This approach stems from the research of Project Zero at the Harvard School of Education and involves the synergic interaction of two frameworks: Visible Learners and Making Thinking Visible. The article focuses on the results of research aimed at understanding teachers' perceptions of using documentation as a research tool in relation to their professional development, within a transformative professional growth perspective.

Documentation was used in the classroom to make visible those "aha moments" in which students realize they have understood a concept. Conversely, it also helped highlight moments of difficulty that often remain opaque and need to be analyzed to understand what is not working and preventing students from grasping the concept.

During the project, among other working tools, a discussion protocol known as the “Protocol for Collaborative Analysis of Documentation”was used. This protocol facilitated the creation of a learning environment favorable to guided discussions on a documentation excerpt, structured around a research question—mirroring the approach of researchers. The protocol fosters structured discussions by allowing a small group to engage in an in-depth conversation while others observe and reflect before contributing. This approach not only encouraged critical analysis of documentation but also promoted a shared professional learning experience among teachers.

The paper will examine qualitative evidence gathered from the eight collaborative documentation analysis sessions conducted throughout the project. This evidence will be interpreted in conjunction with the results of a questionnaire aimed at assessing whether, and to what extent, this work has influenced teachers' professional stance.
Finally, this article aims to highlight the innovative nature of a project in which four geographically distant schools collaborated online to conduct fishbowl sessions. Thanks to the recordings, this process made a vast corpus of materials available for analysis from a research perspective.

Keywords: Making Learning and Thinking Visible, Teacher professional development.