HELLO It didn’t take my 10-year-old son, Oliver, long to get the meaning of that magical word “all-inclusive.”

Me: “Well, it’s not really that everything’s free. What it means is...”

Oliver (interrupting, as usual): “Mom, mom, OK if I just go back to the bar for another smoothie? It was so good.”

All-inclusive means plenty more at the 388-room Iberostar Paraiso del Mar, just 15 miles south of the Cancun airport on Mexico’s Riviera Maya. The resort pops up from the scrubby coast like an oasis of palm trees, trimmed lawns, and treed gardens. Its most notable feature is a series of interconnected pools that starts with a thundering waterfall at one end and runs through the property—in shallow lagoons, a water volleyball pool, hot tubs and swim-up bars—to the beach. Nowhere is the water deeper than 4 ft. 7 inches, so I never had to worry about my five-foot-tall son.

The buildings lend more than a touch of fantasy to the site: the colorful, open-walled lobby sprawls forever, with rattan furniture, high domed ceilings and gleaming marble floors. Beyond are ponds where fountains splash and flamingos stalk about. Footpaths wind through the property, marked with smooth paving stones. Brief daily rain showers keep the vegetation lush, and everywhere there are birds: singing, peeping, chirping, and squawking.

The pool area, with a multitude of chaises, and bars serving smoothies, ice cream, beer, and the like, is flanked by three-story buildings housing guest quarters. The comfortable rooms have spacious baths and free mini-bars full of soft drinks and beer. At the far end is the sea, with a gorgeous beach. During our stay the red flags were up because of high winds, but that didn’t deter scuba divers: we saw an excited group preparing to head out one gusty morning.

Oliver adds, “I like the really good food, the really big swimming pool, and the pool with the swim-up bar.” He’s right, this place is ideal for kids. Pretty much everybody congregates at the pool, where a gently sloping section is appropriate for the youngest toddlers. The children’s program, Lucy’s Kids Club, has its own air-conditioned building with a wading pool and jungle gym. Our greeting by a clown in full makeup failed to impress the boys in my group (one 9-year-old and two 10-year-olds), but may amuse younger tykes. (The club caters to kids ages 4-11; there’s also a teen club operating in summer.) Some 35 people are employed to entertain guests, and they roam the property at all hours, some in costume, thinking up outlandish activities. At nighttime, the theater holds a half-hour disco for the kids at 8 pm, followed by an elaborate musical theater event, usually involving some audience participation.

The Spanish-owned resort attracts both North Americans and Europeans; groups of adults and extended families; it’s great for a family reunion. (After our return, I learned that a fellow soccer mom had come to Paraiso del Mar with about 20 members of her family. She and her boys—then aged 8, 6, and 3—had had the time of their lives.)  Iberostar Hotels and Resorts in general have received a Crystal Award for Best Hotel Chain from an Apple Vacations guest survey for six years in a row.

Of course, meals are especially easy at an all-inclusive. Here food is available around the clock. Breakfast meant an almost overwhelming buffet at La Plaza: besides the usual American necessities, a full range of Mexican dishes, unlimited fruit and, in Oliver’s case, pancakes with chocolate syrup and all the bacon and sausage he could eat. Five dinner restaurants require reservations and are slightly more formal (i.e., trousers are required for gentlemen). We loved La Hacienda, with its Mexican decoration and excellent food, all freshly prepared with local ingredients. The boys scarfed down platefuls from the appetizer buffet then ogled the dessert buffet, earmarking chocolate treats they planned to devour. Other dining rooms serve Brazilian food (El Rodizio), Japanese, and Mediterranean (including pastas and seafood).

Three-year-old Paraiso del Mar has yet to show its age, but such a large and lavish property requires constant upkeep, and Spanish-owned Iberostar has pledged to keep reinvesting. They’re also expanding the so-called Iberostar Playa Paraiso Resort complex: after opening Paraiso del Mar and Paraiso Beach in 2000, they built the adjoining Paraiso Lindo in 2003. December 2004 saw the debut of its twin resort, Paraiso Maya, this time built to imitate the El Castillo pyramid at Chichen-Itza. Each resort has been more upscale than the last, with more pools, more room amenities, and more teak and marble. The P.B. Dye golf course, shopping center, spa and fitness center will complete the Maya's luxurious facilities for now.

How do the Paraiso del Mar and Paraiso Beach compare? They are essentially the same resort, sharing that long pool but having separate reception areas and their own rows of guest-room villas. Why the two names? The big tour companies prefer not to book the same resorts as each other, so Iberostar operates here under two different names. Guests can visit the same restaurants, and there’s virtually no difference in the rooms (or price) at the two places.

Don’t miss two of the local excursions during your stay. The ruins of the extraordinary Mayan city of Tulum are about an hour’s drive south, not on the usual dusty plateau but on a 45-foot limestone bluff above the sea. Of its 60 structures, El Castillo is the most prominent. Start early for this expedition, because the site gets hotter and more crowded as the day goes on. And bring bathing suits: this will be your only chance to swim within site of a Mayan ruin!

Xcaret (pronounced ish-KAR-et) is a Mayan theme park covering some 320 acres (wear walking shoes) where you can tour authentic ruins, visit an orchid farm and see zoo enclosures housing jaguars, tapirs, manatees in pools, hawksbill turtles and more. For Oliver, "My favorite thing was swimming with the dolphins. I liked the parrots when they grabbed my hat. The underground river was really cool, too.” I agree. Donning life vests and snorkel gear, we swam for some 40 minutes in a deep, dark, slowly flowing stream of refreshingly cool water. Occasional openings in the tunnel-like ceiling let in glimpses of sky, and at several points there are steps that allow you to cut the trip short—but no one does. The swim ends at a breezy point on the ocean, where dozens of white hammocks swing among the palms.

Iberostar Paraiso del Mar and Paraiso Beach Resorts, Riviera Maya, Mexico www.iberostar.com 888/923-2722,  305/774-9225 $$ - $$$$     A     A+     A    A Extra Credit: The pool - or rather, pool complex - is a thrill for water-loving kids of any age. Comments: Many family-friendly activities in the area make this a great destination for a week's stay. Rates: A terrific value with a 7N all-inclusive stay, including airfare from major US cities and airport transfers, ranging from $1,200-$1,500/adult during high season. (Kids under 12 pay airfare only.) Iberostar properties can be booked by your travel agent.

Canadian-born Barbara Peck has covered travel as an editor and journalist for several major publications. She lives in New York City, and especially enjoys taking her family (sons Evan and Oliver and husband David) on the road with her.