Before you kids drop two g's on summer camp, be advised.
The pacific northwest region, including hood and whistler, is having the worst snow season in many decades. All of the ski resorts in Washington state are close due to lack of snow.
The summer camps at Whistler are held on the snow that falls on top of the Blackcomb glacier, not the glacier itself. It's very difficult to sculpt a jump out of solid glacial ice. Hood also relies on the natural snowfall that blows around at the high elevation and fills in it's canyons for thier camps.
SO unless we get dumped on in February and March, I wouldn't count on summer skiing lasting past May.