Ilka Dias Bichara is an associate professor at the graduate program in Psychology of the Federal University of Bahia, Brazil. She holds a PhD in Experimental Psychology from the University of São Paulo, Brazil, and has experience in Etiology and Psychology of Development, focusing on Attentional and Cognitive Processes and developing researches on the following subjects: children's play, contexts of development, make believe play and peer culture. She is one of the coordinators of the working group “Play, Learning and Health” of the Brazilian National Association for Research and Graduate Studies in Psychology (ANPEPP).Celina Maria Colino Magalhães is a full professor at the graduate program in Theory and Research of Behavior of the Federal University of Pará, Brazil. She holds a PhD in Experimental Psychology from the University of São Paulo, Brazil, and has experience in Developmental Psychology, developing researches on the following subjects: child development,toy libraries, interactions and shelters. She is one of the coordinators of the working group “Play, Learning and Health” of the Brazilian National Association for Research and Graduate Studies in Psychology (ANPEPP).