A National Parks Pass

Eighty bucks. That's what this will set you back. And in return, it will provide you, three additional adults, and all the kids under 16 you can fit in your vehicle with access into nearly 400 units of the national park system. Tell me a theme park that offers you such a return on investment. And once you leave a park, if you hold this pass you don't have to pay to get back in. In fact, no one in your car has to pay to get in.

Free Entertainment

Travel to Yellowstone, and you can spend hours, or days, watching Old Faithful and its fellow geysers spit and fume and boil and hiss. You also can keep count of all the elk, moose, wolves, bison, bears, and other wildlife that you see. Spend a few days at Cape Hatteras National Seashore and you can mesmerize yourself watching the waves roll in to shore, count the seabirds, or simply walk the dunes. Go to Yosemite and you can watch some of the world's tallest waterfalls plummet wispily into Yosemite Valley. Travel a bit south to Sequoia and you can see some of the tallest trees on earth. Go to the northwest and into Olympic and you can marvel at basically three parks in one, what with the Pacific beaches, temperate rainforests, and high, glacial-covered alpine reaches. And the charge for these activities? Nothing once you get in the gate.

Fresh Air and Exercise

These two amenities are getting tougher and tougher to find these days. Fortunately, travel to a national park and you're likely to find some of the freshest air in the country, and plenty of exercise to go along with it, exercise that you don't always appreciate you're racking up because you're so busy enjoying your visit.

Getting Back to Basics

Okay, this is one of those touchy-feely, amorphous kinds of rewards of a national park vacation. Pack your kids into the car, tell them they have to leave the video games and iPods behind, and once you reach the park of your choice you can get to know one another better by actually communicating face-to-face while enjoying a hike, paddle, or quiet dinner. National park vacations are perfect for bonding with your teens, particularly if you share your experience mountain climbing or backpacking or sea kayaking.

No Closing Time

Parks are open 24/7 every day of the year. There's no closing time. You don't have to go to bed when the sun goes down. In fact, some times it's more enjoyable to stay up, watch for shooting stars, or listen for owls.

Go at Your Pace

You can be as organized, or as laid back, as you wish on a park vacation. You can rise with the sun to get out on the trails before anyone else, or sleep in and enjoy a leisurely breakfast while others are out beating the trails. You can sign up for a naturalist-led course in sketching or wildflower identification, or sit back in a tour bus and let someone else drive while the guide tells you what you're seeing.

Learning without Realizing It

It surely must be a scientifically proven fact: Kids learn more when they're having fun. That's part of the beauty of ranger-led hikes and programs where kids have someone other than their parents to bounce questions up against. And where those rangers fire back with their own set of questions that force kids to learn all the while that they're having a great time. Check out any park's supporting nonprofit foundation and you'll find a slew of programs that range from a few hours to a week or more of family-oriented activities that will help you bond with your kids while you all learn something.

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