Well done for not contraicting Mr Ammie in front of Little Ammie - confused messages will do more damage then good.

Jesus - "Your're off the team!"

Taking a very English point of view, this sounds like something from those terrible sports/high school type movies you occasionally send us!

If he likes it, encourage all the way. If he's ont, then explain to him options, and why you both think he should keep doing it. But also that these is more to live than sports, and those that think there isn't...well....they clearlt dont smoke pot now!