It pays to do your homework when planning a trip with this hard-to-please group.

Getting into the psyche of a teen's mind may not be your top priority when planning a family trip with your "young adult" in tow. However, since teens' likes and dislikes are constantly in flux, we've teamed up with family travel expert, Luisa Frey Gaynor, and her 14-year old, well-traveled daughter Alex Gaynor (Teen Editor of CruiseMates.com) to get their fool-proof teen favorites.

Water parks: Whether you visit an indoor or outdoor water park, these action-packed spots will create quite a splash with your teens. Most water parks these days are quite extensive, which leaves little opportunity for comments such as "this is lame."

"Cool" Cities: Some cities have that special panache that helps deem them "cool" by teenagers. "My favorite cities to visit in the U.S. are Seattle, San Francisco, and New York City," said Alex Gaynor. "They all have a cool atmosphere, great restaurants and attractions that aren't boring," she continued.

Cruising: While to some teens, cruising means driving with their new-found car license, those who have sailed on one of the newer ships at sea know what cruising really means: late night pool parties on deck with other teens; hanging out at the high tech teen rooms; and even climbing rock walls, playing basketball and surfing. "You can't go wrong with a Royal Caribbean Freedom-class ship," said Alex, who has sailed on over 30 cruises. "Other teen favorites include Carnival Cruise Lines," she noted.

Theme Parks: Small doses of theme parks are a good fit for teens too. Look at the waiting line for the latest, highest, and fastest roller coasters at theme parks, and you'll see plenty of teens there -- that's because they thrive on action and adrenaline-pumping activities.

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