Final answer:
A Y.M.C.A. or Boys/Girls Club is a Tier 1 organization suitable for children in middle childhood to participate in peer-group activities that aid in social and physical development.
Step-by-step explanation:
A Y.M.C.A. or Boys/Girls Club would likely be considered a Tier 1 type of organization when it comes to formal peer groups. These institutions provide structured environments where children, especially those in middle childhood, can engage in activities that promote socialization, cooperation, and physical health. For instance, from the ages of six to ten, children begin to play in mixed-gender groups and participate in team sports or groups like scouts. Peer groups at organizations like Y.M.C.A. or Boys/Girls Club present ideal opportunities for children to develop these skills while participating in group activities and sports.
Additionally, being part of structured extracurricular settings can help children to shape their social identities, which can be linked to the perception of belonging to a certain social class, as indicated by members of a club in the Figure 9.9.