The kids and I just climbed Shasta last week (10/11/13 yrs old). I wanted something light, waterproof, didn't give them blisters, and that could be used with light crampons.
I ended up going with light, waterproof hikers (Keen, Eddie Bauer, etc.) and they worked great. With gaiters our feet stayed mostly dry until the end (~3000' of glissading) and none of us got blisters or even hot spots in 14,500' of climb/descent.
We brought Stubai ultralight crampons but ended up not using them, but during the fit checks on the boots they seemed to work very well and of course are light, which is key for kids.
BTW we plan to use the same setup on Rainier later this summer. My days of climbing in my plastic boots are over except for very technical routes that require rigid crampons.
ABTW...Stubai is amazing. I have size 15 feet and their crampons were too short and after a quick email they shipped me a new set of longer bars in a few days for free.