I'm from Frisco and my freshman year in HS was the year they "Rac"ed our Coons...and I don't think an NAACP group was the source of the change, it started with a really angry parent who's two black kids went to school in Frisco (I played football with them) and pretty much single handedly influenced the Coons be changed to the Racoons.
I felt pretty sorry for the kids, they caught a lot of crap for it, but it didnt really change much, the only people in the town who actually say Racoons are all the teachers.
On a side note I was born in Bay City TX, home of the Black Cats, but in junior high we were the kittens...