Yeah, both of mine have used both hands to draw with when little too. I don't encourage either one, i.e. if I hand them a pencil I will just put it in front of them to take, not to one hand. DD1 though favours her right hand more often now though and has never been to childcare or kindy. I would just ask any teacher not to try and encourage him to choose his right hand, just leave it up to him. They should do that anyway though I would think.