(photo: Smugglers' Notch, Vermont)
Want a guaranteed way to beat the heat? Pack up the kids and hit the slopes. According to the National Ski Areas Association, more than half of U.S. ski resorts now offer summer pursuits from zip lines, alpine slides, and summer tubing hills to mountain biking, bungee trampolines, and disc golf. What else can you look forward to? Stellar views, cooler temperatures, and fewer crowds than you'll likely find at the beach. Here's a sampling of some of the top kid-friendly mountain resorts and what you can expect to find.
Smugglers' Notch: Jeffersonville, Vermont
Love the water? Smuggs, as it's affectionately known, has eight heated outdoor pools, four water slides, and a variety of water playgrounds for both younger and older kids. Rum Runner's Hideaway is a six-acre reservoir where you can canoe, paddleboat, fish, swim, or jump on a giant water trampoline. Smuggs also offers one of the best and longest zip-line canopy tours in the United States, along with a tree-climbing program and treetop obstacle course.
Keystone Resort: Keystone, Colorado
Hiking and biking aren't the only way to get around this Rocky Mountain resort. Keystone has its own stables and offers horseback riding and pony rides. You can also take guided river rafting tours on the nearby Arkansas or Colorado rivers. Looking for kid-friendly activities that are more low-key? On Tuesdays through the middle of August, Keystone offers Discovery Days with different entertainers and activities from puppeteers to visitors from the Denver Zoo. And on Friday mornings the local Lake Dillon Theatre Company brings its show up to the mountain with performances of a family-friendly musical in the resort's amphitheater.
Park City Mountain Resort: Park City, Utah 
(photo: Park City Mountain Resort, Utah)
Hold on tight, thrill seekers. Older kids and teens will make a beeline for the ZipRider, which zooms 100 feet above the slopes at up to 45 miles an hour, while the whole family can ride Park City's 3,000-foot alpine slide -- one of the world's longest -- or the alpine coaster, which offers 4,000 feet of curves and loops. There's also lift-serviced hiking and mountain biking and an Adventure Zone that challenges kids with boulders and a climbing wall. Meanwhile, younger children can enjoy a carousel or miniature train ride at the Little Miners Park.
Northstar: Truckee, California
Like to golf? Northstar's Robert Muir Graves-designed par-72 course is a doozy, with two nine-hole settings that show off the sensational mountain and meadow surroundings. Drop off your children in the Kid's Adventure Club, where they can learn about bird watching, wilderness survival, local plant life, and forest fire prevention through fun activities like scavenger hunts and nature journaling. When you regroup, take your pick of outdoor roller skating, mountain biking, gem panning, mini golf, or the ropes challenge course.
Sunday River: Newry, Maine 
(photo: Sunday River, Maine)
A trip to Maine without lobster? You bet. This eight-peak inland resort offers a zip line, bungee trampoline and disc golf, plus a bike park with 20 miles of lift-serviced terrain. Looking for something more sedate? Bring your GPS (or rent one there) and try a geocaching adventure along the resort's hiking trails.
--Mara Gorman of The Mother of all Trips contributed this to MiniTime.com.