<p>Maybe it’s different in NYC, I don’t know. I can say definitively, having lived here for 30 years and raised a kid here, that letting a 9-year-old ride the subway alone in Boston would certainly not be “the extreme of irresponsible and foolish.” Not even close. It would indicate a fair amount of confidence in the kid’s maturity and resourcefulness, but many kids <em>are</em> that mature and resourceful at 9, and no one can make that call better than the parent.</p>
<p>I might add some caveats: I would only let a kid that age ride the subway in the daytime; I would only let them ride between stops serving places they knew reasonably well–i.e., I’d let them ride from home to school, or from home to a friend’s house or a museum, but not to some random place they have no familiarity with. And I’d make sure they had a charged cell phone and knew how to use it.</p>