IN THE AIR
Put it on Ice: Fly Icelandair via Reykjavik, Iceland, to break up your journey into manageable segments. You'll appreciate the leg-stretch as you await your connecting flight. Or, schedule an extra night to take in some of the sights of this unique sub-Arctic moonscape! But even if you only have a half-day layover, many of the country's famed all-natural hot springs--include The Blue Lagoon--are within a short radius of the airport (you can even "rent" bathing suits).

Doctor DVD: Pack a portable DVD player and a selection of the kids' favorite movies for the flight. Sure, books and coloring books are right-on, but you can bet that having the power of the remote will buy you (and your fellow passengers) several hours' grace if the in-flight movies don't cut it. (Just remember to juice up those batteries—nobody will appreciate a mid-flight power lapse…and ensuing tantrum.)

Snack Attack: For toddlers, eating is a prime plane-time activity. Raisins, Cheerios mixed with Teddy Grahams, assorted fruit…these snacks will help tide over hungry tots between meal servings. For older kids, too, pack some sandwiches, fruit, or favorite snacks—never a bad idea. Be aware of TSA travel rules; however, and err on the side of caution. While restrictions pertain mostly to liquids, travelers should pack snacks in three-ounce or smaller containers. Visit www.tsa.gov for more details about what you can and cannot carry through U.S. airport security.

Second Skins: If you're not traveling with a change of clothes for Junior, you can bet that the OJ is going straight into his lap. Pack a clean outfit in your carry-on baggage for countering those unavoidable spills. You wouldn't want to sit in a puddle of milk for two hours, would you? Also, pack some plastic or Ziploc bags for stashing any wet gear.

ON THE GROUND
Heathrow, No Go: Avoid London Heathrow if you can. This busy airport often spells headaches galore for hassled parents dragging tired kids and assorted kiddie paraphernalia like car seats and bulky diaper bags. You must walk seemingly miles of corridors after disembarking, certainly not thrilling after a long overnight transatlantic flight. Instead, consider traveling via smaller airports like London Gatwick, London Stansted, Manchester, or Glasgow.

Cheap and Cheerful: Invest in a cheap umbrella stroller instead of hauling that $800 Bugaboo or bulky collapsible with you to the Old Country. These $20 steals are great for transiting through airport terminals while children slumber, plus they do double-duty for wheeling rucksacks and bags when the wee ones want to wander. You won't mind ditching it at the end of your trip if it gets dinged by a careless baggage handler en route.

Museums 2.0: Ditch that urge to do Britain by the book. Instead, get creative with activities like a British Museum sleepover—snuggle up to Egyptian mummies—or a tour of Concorde at the Museum of Flight outside of Edinburgh. Check out the Kids in Museums campaign (www.kidsinmuseums.org.uk) for more fun museum-centric ideas around the British Isles.

Tube Time: If you're visiting London, know that the Tube becomes a mob scene during morning and evening rush hours, so best to avoid it with kids in tow. Some of the older stations have narrow staircases and often no elevators or escalators, making them a nightmare to enter with strollers and travel luggage. Don't rule out the bus, a less stressful, cheaper way to go. Plus you get to see the street-level sights.