Adolescence is a volatile developmental period in which peers, and especially close friends, take the spotlight in influencing behavior and learning. A common developmental disorder in adolescence...Show moreAdolescence is a volatile developmental period in which peers, and especially close friends, take the spotlight in influencing behavior and learning. A common developmental disorder in adolescence is attention-deficit/hyperactivity disorder (ADHD), which might also influence learning in the peer context. Although research on observational learning has shown that children learn better from their peers than from adults, little attention has been paid to adolescents and the role of different peer relationship types, friendship quality, and ADHD symptoms. In our study, 203 adolescents aged 10–15 years performed an observational reinforcement learning task in four conditions (i.e., individually; with a friend; a known neutral classmate; an unknown peer) and filled out sociometric nominations and questionnaires measuring friendship quality and ADHD symptoms. Results showed that adolescents learned significantly better from a peer than individually, but there was no difference in learning performance between the social observational learning conditions (i.e., friend; neutral classmate; unknown peer). Furthermore, there was no significant interaction effect of peer relationships and friendship quality on observational learning, and the relationship between ADHD symptoms and observational learning was not mediated by friendship quality. However, ADHD symptoms had a significant negative effect on observational reinforcement learning. These findings show that adolescents benefit from learning from a peer, regardless of the relationship with that peer, encouraging the implementation of peer learning in education. Finally, the results indicate that individuals with ADHD symptoms are potentially disadvantaged in their ability to learn from peers, highlighting the importance of developing interventions to foster observational learning.Show less