I work in an elementary school (grades K-7) and have noticed this fashion trend as well. At first, I told myself to chill out, that I was reacting just because I was thinking in terms of what little girls wore when I was a child. I still find it a little unnerving, though, a little "rough" when both boys and girls wear this all over their clothes.
What really threw me was when, one day circulating around a grade 4 classroom while students were drawing and working on art projects, several of the little girls were doodling skulls and knives. They thought it was cool.
In my day (and I'm not that old!) it was flowers, animals, hearts, names, etc.
Eek...
Nenuphar