How to teach my big pup to play gently with my small dog and cat?

I just got a 3 month old lab puppy and he is beautiful and can be boisterous like most lab pups. I am also taking him to obedience classes and practicing skills every day. My only concern is he is so eager to play with my 1 year old maltese and my cat- and they enjoy playing with him- but then he gets carried away and too rough. I have tried saying NO! and putting him on a lead each time and have also tried redirecting his attention to me, getting him to sit then throwing a fave toy for him ect. but as soon as I let him go- he is straight back chasing her and jumping on her. He is already quite a bit bigger than her so I would really like to break this habit. He does the same to my very dog-friendly cat and I am scared someone is going to get hurt. Also how do you tell the difference between normal puppy roughness and dominant behaviour?