If you have picked a good coach for your little duster he should be teaching him good body positioning and solid edge work. Everything will fall right into place providing your duster can take a little bump along the boards.
When do we starting preparing our PeeWee Major for the hitting? Clinics in the summer? Is there hitting at Spring Tryouts?
For clinics are any recommended?
A little early to be thinking about next year but regardless, if your son's coach isn't teaching them body positioning, staying tight to the boards, etc. today, than you are going to want to find some clinics ahead of tryouts. Some org's allow & encourage hitting during Bantom Minor tryouts, others don't so there is no hard & fast rule. If your son hasn't been exposed to checking, getting accustomed to it during tryouts isn't ideal but in total candor, isn't the end of the world either.