D.P.
I think it's very common that they master #1 before #2. Explain that poo is waste from the food we eat and all of the vitamins are out of the food now. Tell him it is not "part" of him. Tell him it's good to get the waste into the potty. Get "Once Upon A Potty" (boy version) book. Something definitely clicked for my son after that book. Let him look at him bum in the mirror so he can see where the poop comes from. I think pooop is more mysterious for boys! LOL Good luck!