* co-op
* Ballet
* Fencing
* Gymnastics
* Math Circle
* Church / Fellowship
* Neighbors
* Family & Friends
That easily adds up to 50 children their age.
But my thinking isn't really about the numbers of socialization. Public school academics move at a glacial pace. They don't have a sufficient rigor, lack a decent education in mathematics, neglect the classics and philosophy, and have started to neglect the western canon in favor of contemporary literature which is poorly written and offers little value. There are also, even in the best schools, trouble students that disrupt classrooms.