DWR MASS,
You asked about youth hockey in Zürich area....
My 14 and 12 year old sons play for the ZSC Lions Club... As they started their hockey careers in the US, we also skated year round as your son does...
Here in Zürich they melt the ice (I mean the indoor ice as most of the practices take place outdoors from October till March!!) end of March. Our teams travel to some international tournaments in spring, not in the summer. Through the summer the teams mainly do off ice training + they have their team camps on ice for a week or two during the summer out of the Zürich area.
Last summer someone recommended the following camps when I was looking for more ice during the summer. I have no experience with these as we ended up traveling back to US:
www.verbier-hockey-school.com
Summer hockey camps in beautiful Verbier with mountainbiking, swimming etc. with international participants, language mainly french but also english. Beautiful location for a family holiday.
www.abhockeyschule.ch
Summer hockey camp at Sports-Center Huttwil, mostly swiss participants. All professional coaches, excellent pre-season preparation.
Hope this helps,
FinnMom