This book celebrates the 15^th anniversary of the bi-annual symposium series Mathematics and its Connections to the Arts and Sciences (MACAS), which was first held in 2005 following the continued collaboration of an international group of researchers from ICME Topic Study Group 21. The MACAS-conferences bring together scientists and educators who are interested in the connection between mathematics, arts and science in educational curriculum, while emphasizing on, as well as researching about, the role of mathematics.

By pooling together these different approaches and viewpoints between mathematics, arts and sciences, this book reveals possible synergies and paths for collaborations. In view of the challenges of the 21^st century, a modern approach to education with a focus on multi- and interdisciplinarity is more important than ever. The role of mathematics assumes a key role in this approach as it is connected to all other disciplines, such as STEM education, physics, chemistry, biology, aesthetics and language, and can serve as a bridge between them.

This book discusses, amongst others, the curricular approaches to integrate mathematics and other disciplines, the importance of mathematical modelling and the interdisciplinarity ways for learning and studying of mathematics, as well as the intercultural dimensions of mathematics and mathematics in the digital era. All topics will be presented from very different perspectives and regarding very different contexts, including digitization, culture and sustainability.

This unique collection will serve as a very valuable and compact source for all above mentioned scientists and educators, as well as for use in advanced teacher education courses.

Claus Michelsen (Prof. Ph.D.) is full professor at the University of Southern Denmark in Odense, Department of Mathematics and Computer Science, and former head of Center of STEM Education'. He is one of the three co-founders and co-organizers of MACAS with the organization of MACAS-2 in Odense. He coordinated numerous European and international projects with engagements at different conferences, e.g. ICME. His research concerns to teacher education, here esp. mathematics and science education with a special focus on modelling. He has long experiences as a teacher in secondary school in Denmark, and as Vice-Dean and Director of the PhD-Program at the Faculty of Science at University of Southern Denmark.

Astrid Beckmann (Prof. Dr. rer nat. habil., Dr. h.c.) was born in Berlin. She is professor for mathematics and mathematics education at the University of Education in Schwäbisch Gmünd, Germany. She is supervisor of numerous doctor theses and coordinator of international research projects and conferences, e.g. MACAS, the European project ScienceMath and the actual project MathEdu-Digital. She is one of the three Co-founders of MACAS with the organization of the first and the 10^th anniversary MACAS-conferences at the University of Education Schwäbisch Gmünd. Her scientific work concerns interdisciplinary mathematics education in connection with physics, language and computer science as well as digitization. Also, she has long-term experiences as a teacher for mathematics and physics and as a physicist at the University of Frankfurt/Main. 2010 - 2018 she was university-president and she was president of the rector´s conference of the Universities of Education in Germany.

Viktor Freiman (Prof. Ph.D.) is full professor at the University of Moncton, New Brunswick, Canada since 2003. All the years his main research interest concerns to innovation in school, esp. in mathematics education, talent development, problem solving, and digital competencies. This work lead to numerous publications, books, book chapters, and articles. For instance, the book on Creativity and Technology in Mathematics Education and Computations and Computing Devices in Mathematics Education. He coordinated numerous national and international projects for implementing ICT funded, among others, by the Social Sciences and Humanities Research Council of Canada. Founder of many scientific networks, he was co-organizer of MACAS since 2007 with the local organization of MACAS-3 in Moncton in 2009 and MACAS-7 in Shippagan in 2022. He is president-elect of the International Group on Mathematical Creativity and Giftedness and co-Editor of the Book Series Mathematics Education in the Digital Era with Springer.

Uffe Thomas Jankvist (Prof. PhD) is professor at the Danish School of Education at the Aarhus University in Copenhagen, Denmark. His professorship includes special responsibilities in mathematics education. At the Danish School of Education he is PhD program director of didactics. He was Visiting professor at the Uppsala University in Sweden, IPC Chair of CERME 2019 and organizer of MACAS-2017 at the Danish School of Education.

Annie Savard (PhD, Ass. Professor) is associated professor in mathematics education at the McGill University, department of integrated studies in the faculty of Education in Montreal, Canada. She has long-term experiences as a teacher in elementary school and she as an author, consultant and trainer for the Ministry of Education, Recreation and Sports in Québec, as well as for various school boards and international research and development institutes. Her research interest mainly centers onto the development of mathematical skills. She organized MACAS-2019 at McGill.