re: What's the smartest dog breed?

Maybe you guys can suggestion a breed. We have 3 younger children - 2 girls & a boy. The girls are fine around dogs but the boy likes to rough house with them like he's the alpha. It's rare but he has been bit. He just fusses at the dog but once he bit my in laws dog back. Funniest shite I've seen.
I'm thinking sturdy, laid back but with a bit of playfulness. It's been along time since I've had a dog just looking for a direction.