As a kid, it's very easy to make friends. You don't need school for that. Three of my child hood best friends were not in my schools. I sill visit one regularly, 20 years later.

In fact, I'll argue that school distort the child ability to socialize, not improve it. Because it's an artificial setup were the crazy values and rules only exist and make sense in the school. And worst, adults sell you values and rules from the real world while you are stuck in this alternate dimension.