What is the name of this book series?

Question

When I was in middle school, I used to read this series of mystery books. It was a group of kids that went around solving mysteries. If I remember correctly, they always had a dog with them. One of the kids had some sort of sleep disorder. That's all I remember. Does anyone know what I'm talking about?

Answer 1

Melissa Cleary wrote such a series, maybe your favorite.  "Hounded to Death" was one of the titles.

Answer 2

The dog was Scooby Doo? 

Answer 3

Sherlock Holmes?