Which trips are right for your gang, and when?Presenting a Travel + Leisure Family guide to the best, most seamless getaways—wherever your kids stand on the growth chart.

Aaron Leighton The age-appropriate vacation

When it comes to family travel, one size most definitely does not fit all. The needs of parents making their first anxious foray with a baby are very different from those of a well-traveled clan with high-energy grade-schoolers. And what about families grappling with a teen for whom one wrong move (admit it, Dad, grabbing the karaoke mike was a mistake) can spell M-O-O-D?To understand the requisites—and foibles—of every age group, we polled child-development specialists, travel agents, outfitters, and our own readers and staff. Here, a vacation road map for the years ahead—parental sanity guaranteed.

Although there may well be dauntless parents who would think nothing of mounting, say, a temple-to-temple Bhutan trek with their baby in a backpack, most of us are best off focusing on ease—and napping opportunities. Cherubs who adapt well to change are, of course, the best travelers, but even high-maintenance types benefit from new scenery. Book nonstop flights, and for safety, spring for a seat for your child (and lug aboard a car seat, too). But first, take your pick from these eminently doable getaway options.

Rent a Vacation House

Think of it: space for all that gear, a kitchen, a washer and dryer—and perhaps room for a doting grandparent or two. Rent-by-owner Web sites like www.vrbo.com have thousands of family-friendly options in vacation spots from Anchorage to Zihuatanejo. Or leave the legwork to the pros. Rental agencies such as ResortQuest (800/467-3529; www.resortquest.com) list properties throughout the U.S. and Canada. Ciao Bambino (866/802-0300; www.ciaobambino.com) plans villa vacations in Italy and France; it stocks the house with toys, snacks, and baby equipment; arms you with a mobile phone; and puts you in touch with experienced sitters.

Check into an All-inclusive

This is the cake-mix vacation—all the ingredients you need, just add sunblock. The Club Med resorts at Sandpiper, Florida, and Ixtapa, Mexico (800/258-2633; www.clubmed.com; one week for a family of four at Sandpiper from $3,855, at Ixtapa from $2,595), provide child care in their Baby Club Meds (expect to pay a weekly supplement of about $180 per child). Parents also have access to fridges and microwaves and, as part of the just-introduced baby welcome service, will find their rooms stocked with cribs, strollers, and infant tubs and childproofed. At Beaches Turks & Caicos Resort & Spa (888/232-2437; www.beaches.com; doubles from $865, kids under two free, kids under 15 $90 per night) families can sign on for a $12-an-hour Ultra Nanny who's ready to oversee everything from mealtimes to sand castle construction.

Take a Cruise

Vacations at sea work especially well for multigenerational groups—plenty of opportunities to scatter, and also to gather, especially at meals. Just be sure your cruise is well equipped for the under-three set. Cunard Line's Queen Mary 2 and Queen Elizabeth 2 (800/728-6273; www.cunard.com; seven-day sail for a family of four from $4,196) offer complimentary nursery care from 9 a.m. to midnight, by certified British nannies, for children a year and older. Babies as young as 12 weeks can set sail on a Disney cruise (800/951-3532; www.disneycruise.disney.go.com; four-day sail for a family of four from $1,156), where the Flounder's Reef Nursery staff will look after them for an hourly fee of $6; space is limited, so book ahead. Another Disney plus: children in swim diapers can use one designated (and specially filtered and chlorinated) pool.

Splurge on a Fancy Hotel

Babies are welcome at some of the most sophisticated spots these days. The Ritz-Carlton, Cancún (800/241-3333; www.ritzcarlton.com; doubles from $399)—scheduled to reopen April 30 following hurricane repairs—has Itzy Bitzy Ritz kids' rooms with cribs, changing tables, and phones that light up instead of ring. Cribs with 300-thread-count linens and Mustela baby toiletries await at the Sanctuary on Camelback Mountain in Paradise Valley, Arizona (800/245-2051; www.sanctuaryaz.com; doubles from $525). And at the One & Only Maldives at Reethi Rah (866/552-0001; www.oneandonlyresorts.com; villas from $990), a "villa host" will sterilize bottles and launder clothing, while a chef whips up baby food. Mashed mango, sweetie?

Lighten Up

Find diapers, baby food, and other necessities waiting at your rental house, hotel, or cruise ship. Jet Set Babies (866/990-1811; www.jetsetbabies.com) delivers.

Traveling with kids gets much easier by the time they're five or six, but don't pack that fat paperback just yet. This crowd wants action. They also long to be with kids their age, so pick trips—theme parks, beach and mountain resorts, easy adventures—where you're likely to encounter other families. Or consider traveling with another clan—one whose kids you all enjoy being around. And never underestimate the appeal of a hotel pool.

Do Disney

Prevailing wisdom says that age five is about right for that first mega-park outing, but whenever you go, make sure you have a detailed plan of attack. Former Disney World VIP host Michael Hewell of Tour Guide Mike (321/206-3933; www.tourguidemike.com) charges families $21.95 to map out custom itineraries based on answers to a pre-trip online questionnaire. For the ultimate in hand-holding—at $100 an hour—ask for one of Hewell's guides (www.michaelsvips.com), who will wait in lines for you and snag tables at that Holy Grail of the Disney experience, the Character Breakfast. Stay at the Nickelodeon Family Suites by Holiday Inn (866/462-6425; www.nickhotel.com; two-bedroom suites from $161), which has water parks, arcades, and endless opportunities to be slimed—plus SpongeBob on the other end of the wake-up call.

Take a Wild Adventure

America's national parks (202/ 208-4747; www.nps.gov) cater to kids with junior ranger programs, National Park Passports (get 'em stamped as you go), and free guided family outings. Acadia (207/288-3338), on the Maine coast, is a good first park, thanks to 45 miles of traffic-free crushed-stone carriage paths to bike or hike. For more exotic (and expensive) journeys, hook up with a seasoned outfitter. Backroads' new "unpack-once" Costa Rica adventure (800/462-2848; www.backroads.com; six-day trip for family of four from $12,620) bases families at La Paloma Lodge, on a bluff above the Pacific. On Lindblad Expeditions' 10-day cruises to the Galápagos Islands (800/397-3348; www.expeditions.com; family of four from $13,600), naturalists introduce everyone to blue-footed boobies, giant tortoises, marine iguanas—and to terms like endemic species.

Find a Resort with a Great Kids' Program

Warm juice boxes and broken crayons don't cut it in the new world of resort child care, where hands-on nature and cultural appreciation activities are de rigueur. Beware: most kids' clubs come at a cost—sometimes as much as $125 a day—and some operate only during peak vacation periods. The all-inclusive Tyler Place Family Resort (802/868-4000; www.tylerplace.com; one-week stay for family of four from $4,500), a summer resort in Highgate Springs, Vermont, has lakeside cottages, a spirited overnight-camp vibe, and eight age-specific kids' groups—each with its own activities and dining area. Atlantis (800/285-2684; www.atlantis.com; doubles from $395), the mega-resort on Paradise Island in the Bahamas, teamed up with the Discovery Channel to create a kids' program in which participants feed baby sharks, peer through microscopes, and explore a life-sized re-creation of the lost city of Atlantis. Meanwhile, the six- to 12-year-olds staying next door at the One & Only Ocean Club resort (866/552-0001; www.oneandonlyresorts.com; doubles from $750) are in one of chef Jean-Georges Vongerichten's kitchens, whipping up pizza and guava pudding.

Pony Up for a Dude Ranch

Ranch vacations vary wildly, from spartan to sumptuous. At Dryhead-Schively Ranch (307/548-6688; www.dryheadranch.com; one-week stay for family of four from $4,180), a working cattle farm near Billings, Montana, kids learn roping and roundup techniques. The resort-like Smith Fork Ranch (970/921-3454; www.smithforkranch.com; three-day stay for family of four from $4,600), outside Crawford, Colorado, tutors children in fly- fishing while parents dine by candlelight. Ranchweb.com lists almost 200 locations in the U.S.; greenhorns are welcome most everywhere.

Hunt for Treasure

Give antsy hikers and museumgoers something to search for: buy postcards (of flowers, lizards, works of art), then let your kids lead the quest.

This calls for preemptive thinking. The first salvo: Get the kids involved in the planning stages so they have a stake in the trip—and fewer reasons to blame you when boredom sets in. Browse online together and watch movies filmed at your destination. Don't be surprised, though, if their ideas of must-see attractions—graves of rock stars, sites of notorious crimes—vary widely from yours (which, to them, sound like a forced march through the Musée d'Ennui). To boost the happiness quotient, consider allowing your teen to bring along a friend, and let the two of them, from time to time, strike out on their own.

Volunteer for a Vacation

Want an inexpensive—and deeply satisfying—way to see the world?Wield hammers and power tools for a family in need. Habitat for Humanity (800/422-4828; www.habitat.org) gives volunteers the chance to help build decent, low-cost housing everywhere from the Gulf Coast to Alaska to Tajikistan. Participants have nights off and opportunities during the day to explore their surroundings. One- to two-week trips start at $800 per person in the States, and $1,000 overseas, including food, lodging (often in hotels, but occasionally on cots in schools), and local transportation. Volunteers in Costa Rica and Peru with Cross-Cultural Solutions (800/380-4777; www.crossculturalsolutions.org; one-week trips for family of four from $6,380) assist elementary-school teachers and help people with disabilities—as well as take Spanish classes, explore archaeological sites, and learn to salsa.

Head for a Teen-Centric Resort

Now that hotels have wooed grade-schoolers with kids' clubs and check-in treats, they're out to win the loyalty of their older siblings (who, after all, will soon be paying customers). Pinehurst (800/487-4653; www.pinehurst.com; doubles from $316), the North Carolina golf resort, has a TeenSpa with a menu of facials, massages, and sports training sessions. Family golf packages include a lesson, rental clubs, end-of-day tee times (hence no pressure to keep up the pace), and use of the driving range. San Diego's Loews Coronado Bay Resort & Spa (800/235-6397; www.loewshotels.com; doubles from $265) gives teens goody bags (with a disposable camera, photo journal, wristband that entitles them to free sodas, and list of things to do in the area) and encourages them to blow their allowances in a new surf-themed spa treatment room.

Expedite an Expedition

Outfitters have their eye on young adults and their hapless parents. Butterfield & Robinson (800/678-1147; www.butterfield.com; nine-day trip for family of four from $15,980), which specializes in deluxe trips, has two bike tours aimed at the 15 and older set: one traces the Baltic Coast, the other Spain's Camino de Santiago. Thomson Family Adventures (800/262-6255; www.familyadventures.com; 19-day trip for family of four from $28,160) leads a challenging Kilimanjaro trek for clans with kids 12 and up.

Think Urban

As Petula Clark sang: "Just listen to the music of the traffic in the city/Linger on the sidewalk where the neon signs are pretty/How can you lose?" London is especially easy. Book a suite at the Emperors Gate or Knaresborough Place (44-20/ 7244-8409; www.apartment-hotels.com; suites from $180, two-night minimum), adjacent short-stay properties in Kensington. Take a spin through Hyde Park on Rollerblades: Citiskate (44-20/7731-4999; www.citiskate.co.uk) hosts Friday-night and Saturday-morning sightseeing skates. Catch the tube to Camden Town to shop the outdoor markets (www.camdenlock.net; most open daily) for vintage clothes and one-off duds by emerging designers. And sneak in a museum: the Victoria & Albert (44-20/7942-2211; www.vam.ac.uk) runs one-day design and jewelry-making workshops, $18 each, for 11- to 18-year-olds; parents need not apply.

Be Fresh

Don't be afraid to think exotic with your know-it-all offspring. Foreign destinations or untried activities (skydiving?) level the playing field for everyone.