We're in San Francisco. She was riding the train home from school alone at the end of 4th grade. Someone would meet her where she came up the subway steps.

We live in DC. My 12 year old goes to the rec center near his school after school. He stays until our agreed upon time and then he catches the bus afterwards. He hasn't rode the train alone yet, mostly because the opportunity hasn't presented itself. My now 17 year old starting walking home, about a mile, after school when he was 10 years old. When he started high school he started catching the train/bus to and from school.

OP, are you in DC or the burbs? Maybe it's not common in the burbs but almost all of my kids peers started taking the metro alone in middle school. A few even as young as 4th/5th grade.

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