During the second half of the 19th century, Thanksgiving traditions in America varied from region to region . . . In New York City, people would dress up in fanciful masks and costumes and roam the streets in merry-making mobs. By the beginning of the 20th century, these mobs had morphed into “ragamuffin parades” consisting mostly of children dressed as “ragamuffins” in costumes of old and mismatched adult clothes and with deliberately smudged faces, but by the late 1950s the tradition had vanished entirely.
citing  Nigro, Carmen. “Thanksgiving Ragamuffin Parade“, a blog post which is full of comments attesting to the scattered persistence of the Ragamuffin tradition, either begging or parading, past the 1950s.
When I was in 4th grade, which was my second year at Our Lady of Fatima Catholic school in Jackson Heights, NY (I’d been on the waiting list since kindergarten), my school either held or participated in a Ragamuffin Parade. It seemed to be a well-established tradition, but it must have been an extremely localized one, because my mother, who had grown up in East Elmhurst, an adjacent walking-distance neighborhood, seemed never to have heard of it.
Our costumes were required to be home-made, and they were definitely not supposed to be scary: so no re-using Halloween costumes. We were also supposed to be, well, ragamuffin-y, although this was not as strict a requirement.
My mother brilliantly dressed me as “Cinderella after midnight”: raggedy clothes, ashes besmirching my face, my hands reddened as if from hours of scrubbing, and carrying the bright orange pumpkin-shaped candy carrier, with three large plastic rats poking out of it. I seem to recall that my hands were red from the cold, too! It was the only costume she ever made for me (home-made craftiness not being one of her strengths), and it’s a very fond memory.
(My little brother, less interestingly, was dressed as one of the three kings, wearing a crown and carrying a gold brick, that is, a cardboard brick wrapped in gold tinfoil – to my astonishment, because I’d thought that tinfoil only came in silver. In retrospect, it was probably gold foil wrapping paper… even less interesting!)
As I recall, this was a school-wide activity, at least for the younger grades. Somewhere, I believe I have a picture that was taken of the whole lot of us in the schoolyard before we set off.
We moved from New York to Rhode Island the following summer, in 1970, so I have no later data – I don’t know whether this was the tradition’s last gasp, or why there had been no parade (or had I just not participated?) the first year I’d been enrolled. (I know it was the second year, because my brother was there too: when I was in 3rd grade, he was in kindergarten, and Fatima started with 1st grade.)
I’ve always remembered marching in the Ragamuffin Parade — well, we didn’t march in this parade, you wouldn’t expect ragamuffins to march, now would you? we sort of straggled along in a vaguely chaotic crowd — but I couldn’t remember when it was, and I don’t think I’d ever been told the context or given a reason. (Since when do kids need a reason to dress up and play around, right?)
But I was thinking about it tonight & it occurred to me that the internet probably knew — and lo and behold, it did! I’m fascinated to discover that it was such a local custom.