Participating in outdoor sports in blue spaces is recognized to produce a range of significant social benefits. This case study empirically analyzes the social benefits associated with the School Nautical Activities project carried out in Viana do Castelo (Portugal) in school-age children and adolescents. It consisted of a 4 year program in which scholars took part in nautical activities (surfing, rowing, sailing, and canoeing) in blue spaces once a week during a semester as a part of their physical education course. The methods used for data collection were as follows: (1) a survey answered by 595 participants in the program and (2) five focus groups (FG): two FGs with participants (seven on each FG), two FGs with their parents (eight participants each), and one FG with the physical education teachers (five participants). Interviews were transcribed and qualitative analysis with NVivo software was developed. Results revealed clear evidence on the social benefits for school-age children and adolescents associated with participation in outdoor activities in blue spaces both in the overall health and in all the following analyzed categories: mental health and well-being, education, active citizenship, social behavior, and environmental awareness. More than 40% state that their overall health is much better now (13.4%) or somewhat better now (29.9%) due to their participation in the program. Thus, this article provides support for the anecdotal recognition of the benefits for school-age children and adolescents from participating in sports in the outdoors and especially in blue spaces.