There are many circumstances in which I recommend scouts programs for clients (typically Scouts BSA, Cub Scouts, or Girl Scouts). Scouts BSA (formerly known as Boy Scouts) and Cub Scouts are both co-ed, while Girl Scouts is for girls only.  There are several reasons why I make these recommendations so often, with a rough outline of them below:

Character
The primary focus of the scouting programs is to teach children to grow up to be functional and constructive adults. Because this is a primary focus, rather than a secondary after thought, the values of the scouting programs are built into the day to day activities done by the scouts. A side effect of this focus, is that the youth who are in these programs tend to come from families who believe that these values are worthwhile, and when the scouts do things inconsistent with those values, it is addressed as a significant part of the program, rather than only if it interferes with winning. 

Scope
The scouting programs all use a very wide array of activities to pursue this character development, so the scouts are exposed to many different activities to varying degrees, rather that strong focus on a single skill set. This allows them to develop themselves more broadly, and learn about a much wider array of possible career choices, rather than, for example, a long shot at a professional sports career. Because the program itself promotes such a diversity of activities and interests, the scouts tend to encourage participation in other programs as well, rather than jealously claiming all of the scouts discretionary time for scouting alone. Consequently, the scouts can pursue interests further which they may have first learned about through scouting. 

Scouting is for all
There is no bench in scouts. All of the scouts get to participate in all of the activities, not just those who are best at the activity. As a result, there is no issue as they reach high school age of "having to make the team" in order to continue with the activities. Everyone can do everything. 

Leadership and Responsibility
The scouts programs tend to be youth-led (with the exception of Cub Scouts, where the youth are all aged 5 to 10 years, and cannot yet do so). The scouts elect their own leaders, and the adults meet with those leaders periodically to teach them to lead. Then they step b ack and let the scouts run their own programs. They choose their activities, plan their meetings and outings, set their own agendas and chore rotations, and the adults supervise just enough to keep things safe. consequently, the scouts learn more about leadership and planning in the course of adolescence than most people learn throughout adulthood. 

Cost
Scouting is one of the more affordable youth activities around, and on top of that, the scouting units do their own fund raising, so that a scout can actually earn their own way through the scouting program without the parents having to foot the bill. Another of the maturity benefits of the scouting programs

Safety
Over the past 30 years or so, the scouting programs have developed some of the safest programs around for protecting youth from predatory adults, with concepts such as "two deep leadership" and background checks for volunteers to keep the youth. 

Check out beascout.org for the Scouts USA and Cub Scout programs, 

or 

girlscouts.org for the girl scout programs.