children's center; child welfare facility
A public facility where children can play, learn, and receive support; often used by school-age children after school or on weekends.
After school, the children played at the children's center.
A new children's center has opened in this area.
学童保育 is an after-school care program, often held within a school, whereas 児童館 is a broader public facility open to all children.
Compound of 児童 (child) and 館 (building, hall). The term is modern, reflecting post-war social welfare developments.