your kids will love Smuggs!
Ok, I may be biased, but i'm sure you will love smuggs.
All the info you will need is on their website
www.smuggs.com - takes a while to find your way around the website but everythings there!
Not sure if your kids would need camp or lessons - whether camp is worthwhile or not partly depends on whether they will enjoy the afternoon entertainment or not - youngest one probably will. older two may be better off with group lessons or Max5 lessons.
I would recommend a couple of days of camp/lessons so you get to know the trails and glades - the top part of many 'blue' trails at smuggs would be considered a 'black' many other places, especially if there's ice rather than fresh snow. The trail destriptions on the 'interactive trial map' on the smuggs website give a good idea of what to expect for each one.
your kids will be fine skiing on thier own without you - the trails are all well signposted and if they do get into difficulties the ski patrol, or a passing instructor, will always be willing to help out.
Cell phones may work in the village, depends on which network you use, but may not work at the base lodge. we use walkie-talkies to keep in touch with our kids, or meet at a prearranged time/place periodically.
The terrain parks are all open now, so the boarders should have fun!
you will need to purchase a 'smuggs pass' ($175 total) which gives you access to all the resort activities and facilities, plus discounts off rentals & lessons.
If you are staying on North Hill, West Hill or Highlands Hill you will also have access to the facilities on your 'hill'.
There is a teen center which the older two may enjoy - 12 yr olds can go until 8pm.
The 8 yr old won't be allowed in the swim pool or fun zone without an adult, but the 12 yr olds will be.
For all the kids its perfectly safe for them to travel aorund the resort on thier own using the resort shuttles - my kids have done so since they were 5 or 6.
Grocery shopping in the resort is limited, but there's a Grand Union in Johnson (about 20 mins drive) where you can buy most things.
dining options are also pretty limited in the resort, but we find we manage perfectly well on takeout pizza on the nights we don't cook.
Other tips?
keep an eye on your account every couple of days, the smuggs reservations system has many 'quirks' and all the staff use it differently. Or, if you prefer, pay for everything as you book it - makes things easier when you check out!
all the staff are very helpful - to the extent that they will sometimes answer your question even if they don't know the answer!
make sure you see Marko the magician on the Wednesday - after 6 years we still can't work out many of his tricks!
you will likely be skiing mostly on Sterling/Madonna - best food is in the Black Bear Tavern in the Base Lodge, though service can be slow. Its fine for kids to be in there on thier own if they are waiting to meet you.
The lifts are very, very, very slow!! Wrap the kids up warm, with lots of hand warmers in their gloves - they'll need it sitting still for 15 minutes or more!
If you need rental equipment, try to visit the rental shop late in an afternoon - its quieter then. The rental equipment is mostly ok, they have lots of new boots & skis this season. You may prefer to rent 'demo' equipment from the Base Lodge - you can change this as often as you like to try out different stuff.
Would thoroughly recommend the snowmobile tour into the Notch. Its expensive, but fun if you've never done this before.
If you need a day away from the slopes, I would recommend the Ben & Jerrys factory tour.