Social facilitation/inhibition (SFI) refers to the enhancement or impairment of performance engendered in humans and animals by the mere presence of others. Although long known in social psychology, this phenomenon is poorly documented in school-age children and its implications for education, positive or negative, are largely unknown. Also, its mechanism remains uncertain making it difficult to propose concrete applications in the classroom. VAMOS-Kids! compares susceptibility to peer presence in children, adolescents, and adults 1) behaviorally, to reveal SFI developmental pattern, and 2) neurally, to seek proof that SFI involves the brain attention networks via an ancient mechanism that we share with monkeys. The fundamental knowledge thusgathered could raise awareness that the cognitive consequences of peers’ omnipresence need to be taken into account in children' education and could provide educators with hints on how to optimize social context in primary and secondary education.