The file
Alan Thicke, before he was the dad on Growing Pains, co-wrote this and the Diff'rent Strokes theme with his then-wife Gloria Loring, who sang this one. It's about taking the good with the bad, and it's a song every girl born in the '70s can sing.
The Eastland School, Mrs. Garrett, Blair and Jo, and nine seasons of a theme that got a disco remix in the middle.