Pico
Pico is sometimes known as "Killington's Little Brother", or among insiders, "the anti-Killington".
While Killington is full of hard-charging folks who want to ski "The Best of the East," Pico is the laid-back, crunchy-granola version of a ski area. It's a little small, but there is very challenging terrain here (see Giant Steps for an illustration). There is great in-bounds glade skiing for both intermediate and advanced skiers, and narrow twisty trails off the top -- a taste of old-school Vermont. (When trails had to be cut with hand tools, they stayed narrow!)
Parents of adventurous children really love Pico. Not only is it a friendly place (with adults that are willing to both help and correct), but all the trails eventually lead to a single base lodge. If kids get lost, all they have to do is "keep going downhill" and they'll eventually get back to the lodge.
Pico has to "try harder" to bring a crowd, so you'll find telemark lessons and races there, Vermont Adaptive Ski & Sports, and an outpost of the Vermont Ski & Snowboard Museum.
Pico is generally closed midweek, so it's a great "second chance" for powder days after a big snow.