What kid's show in the 80's was about two girls who didn't get along in school One blonde who was nasty and the other brunette who was nice The title was something like cats and dogs?

The show you're thinking of is likely "Cat's & Dogs," which aired in the 1980s. It focused on the rivalry between two girls, one blonde and mean-spirited, and the other brunette and kind-hearted. The series explored their conflicts and interactions, highlighting themes of friendship and understanding despite their differences.