Does anyone know what kind of skink this is?

I see it frequently and it is fast.

Hack

Hi, Hack! That is a five-lined skink. We have them here in northern KY, too. The young ones have a bright blue tail. I discovered a large adult under my parents' coffee table a few years ago (they live in the middle of the woods) and I felt terrible when he lost his tail as I tried to catch him. Yep, they're fast! I did manage to catch him under a clothes basket and release him back outside.

Happy Birthday!