Boy Scouts is an Earth youth organization.
Both Jonathan Archer and Malcolm Reed were Eagle Scouts in the Boy Scouts. In total, Archer earned 26 merit badges, including a wilderness merit badge given to him after surviving in a New Zealand rain forest. Reed earned 28 merit badges, including an exobiology merit badge that Archer did not earn.
In November 2151, Archer and Reed exchanged stories of being in the Boy Scouts after each learned that the other had been a member of the organization. (ENT: "Rogue Planet")
In the mid-2280s, David Marcus described his father, James T. Kirk, as an "overgrown boy scout". David's mother, Carol, disagreed with this analogy, however, replying, "James Kirk was many things, but he was NEVER a boy scout." (Star Trek II: The Wrath of Khan)