Tamsin Meaney is professor of mathematics education at Western Norway University of Applied Sciences. Her main interest is about social justice in mathematics education, focused on young children and on teacher education. She has worked in teacher education in New Zealand, Australia, Sweden and Norway. She has been involved in longitudinal research studies and has published many books, book chapters and journal articles.Christiane Benz is full professor of mathematics education at Karlsruhe University of Education in Germany. Her general research focuses the early mathematical learning, especially in the domain of arithmetic in the transition of early mathematics education and primary school. Her other main research interest in professional development is linked with a long-term design-research project (MiniMa).Antonella Montone is associate professor in mathematics education at the University of Bari Aldo Moro, Italy. She conducts research on early years mathematics learning and teaching and on mathematics teachers’ use of digital and manipulative artifacts in synergy. She has been engaged in several developmental research projects pre-service and in-service teachers. She teaches in kindergarten and primary school teacher education and PhD fellows in mathematics education.Benedetto Di Paola is Associate Professor of Mathematics Education at the Department of Mathematics and Computer Science, University of Palermo, Italy. His main research interests concern the study of didactic practices in mathematics, from kindergarten to university, from a historical, social and cultural perspective. Author of numerous publications, he has also been local coordinator of several Erasmus+ and Horizon projects in the field of mathematics Education.Michele Giuliano Fiorentino is a researcher at University of Bari Aldo Moro, Italy. His main research interests concerns the development of didactic strategies to reduce early leaving from school. He deals with research related to didactic innovation, innovative teaching methodologies in Mathematics from kindergarten to university teaching. Author of several publications, he collaborates for the professional development of teachers with several national and international research groups.