The 70th CIEAEM conference was held from 15th to 19th July 2018 at Université de Mostaganem – Fondation Djanatu Al Arif, Mostaganem (Algerie). It successfully involved several participants from many countries all over the world. At the conference, researchers, teachers, educators, and students discussed, with a collaborative and inspiring attitude, different significant problems, obstacles and resources related to mathematics education and the important theme of the conference “What is living together?”; they also presented their latest research findings in the several conference activities: plenary talks, working groups, workshops, and poster presentations (forum of ideas).
As in previous CIEAEM meetings, Working Groups constituted the real heart of the conference, they gave to all participants the possibility to fruitfully discuss in critical and constructive ways, in the true CIEAEM spirit, research studies and approaches from different perspectives on the conference theme. This volume contains all final versions of the papers presented during the conference.
We thank all the contributors and the participants to the conference and we are grateful to Younés Aberkane and all the members of the International Programme Committee and the Local Organizing Committee for the realization of the 70th CIEAEM conference. Particularly we want to thank the Working Group animators, who, as in previous CIEAEM meetings, worked in a well high-quality way.