Parmer's Resort in Little Torch Key (just south of Big Pine) is small and cozy yet features a pool, waterfront view, and complimentary breakfasts. Rates start at $99 for a room with two twin beds; $149 for a room with a queen bed; $304 for waterfront rooms with kitchenettes (305-872-2157; parmersresort.com).
La Concha hotel in Key West is perfect for families who want to walk to nearby attractions. The historic hotel is the tallest building in Old Town, nestled in the heart of Duval Street. Babysitting services can be arranged through the concierge, a Starbucks in the lobby will get you going in the morning, and the rooftop bar and lounge provide stunning views. Rooms start at $199 a night (305-296-2991; laconchakeywest.com).
Tranquility Bay Beach House Resort in Marathon is newly opened and offers something for everyone in the family. Water-sports staff will take the kids on adventures, babysitting services are available, and there's a private beach and pool. Two-bedroom beach houses start at $173 per night; $196 for three bedrooms (866-MID-KEYS; tranquilitybay.com).
Cheeca Lodge & Spa in Islamorada offers the ultimate in luxury. Kids ages 5 to 12 can attend Camp Cheeca, which hosts a variety of island activities, while Mom and Dad play tennis, go deep-sea fishing, enjoy a Tahitian-style spa lagoon, or just relax in a beachside hammock. At night, the whole family can enjoy entertainment such as Caribbean rhythm with steel-drum bands and fire dancers. Accommodations for a family of four will cost about $577 a night in high season (800-327-2888; cheeca.com).