Previously (in the post linked to this one), I suggested that the idea of 'upsherin' is to dramatically differentiate a genderless 'babyhood' from 'boyhood'. These bright-line rites of passage can be very poserful, especially for a 3-year-old.
One may then ask why there's no female equivalent. After all, why don't we want to generate positive gender identities in our maidelach?
Perhaps a central element of the feminist critique - that in patriarchies women were essentially defined as 'non-men' - is true for the Halakhic tradition (though it's tough to prove such a claim from an isolated minhag, it may be a bit of evidence). In other words, becoming a girl equals growing up an not becoming a boy.
If there would be an attempt to find a rtie of passage into girlhood - a positively constructed girlhod - in the Jewish tradition, what form would it take? At first I thought, perhaps, ear piercing could be a good option. Let a 3 year old girl get her ears pierced. But then I heard that there's an opinion (can't remembre who/where) that girls get their ears pierced for similar reasons to the 'eved nirtza' - i.e., as a symbol of servitude. Ouch. Maybe not such a good idea. Any other ideas?