The Costa Rica Caribbean zone is warm, rainy-and-sunny, with thick lowland vegetation and a variety of microclimates. Start at the coast on a white sand beach and a few hours later, find yourself in the misty coastal divide, surrounded by extra-large tropical plants and waterfalls cascading from the hillsides. Kids will get a kick out of the quick changes in weather and locale.
Ride the Rainforest Aerial Tram (Braulio Carrillo National Park) - The Rainforest Aerial Tram takes you through the canopy for an up-close view of animals that live in the upper regions of the rainforest. This is a must-see (think how much fun your kids will have with their rainforest report in school). Kids under 5 can ride - special seats are provided for them for a safe and comfortable ride.
Tortuguero National Park (Parque Nacional Tortuguero) - Each year hundreds of turtles come to the beach at Tortuguero to lay their eggs. At night, the female green sea turtles lumber up the beach to dig a hole in the sand, lay the eggs, then cover them up with huge flippers. The sight of these primeval creatures, vestiges of the dinosaur age, is unique. The best time to see the green sea turtles nesting is July - September.
Tip: The 22 mile beach in the national park is a long, lovely deserted beach. Kids can spend hours beachcombing, but no swimming.
Turtles aside, Tortuguero National Park is a wondrous natural habitat. Follow trails through the tropical rain forest, filled with spider or howler monkeys high in the trees (don't wear orange, they might pee on you), bats hiding in the palm leaves, or leaf cutter ants and colorful frogs in the undergrowth.
Or take a boat trip in a shallow-bottomed launch through the network of canals and creeks that crisscross the palm swamps and forests. Bring your binoculars and sharp eyes to spot tiny little Jesus Christ iguanas (they can skip over the surface of the water), a caiman (only his eyes poking above the water), or a boa constrictor coiled on a branch, perfectly camouflaged. You might even catch a fleeting glimpse of a manatee or a jaguar. You're sure to see the busy white-faced capuchin monkeys or colorful butterflies in the forest. The water in the canals is warm, but you won't be swimming (crocodiles also live in the rivers).
The tiny town of Tortuguero has a Visitor Center where can find out more information about the habits of sea turtles and the conservation efforts. At the souvenir shops, pick up a "Tortuguero Field Guide," a laminated sheet with pictures of the common animals found in the area. Wander over to the colorful children's playground to see where the local kids play.
There are no cars in Tortuguero. To get to Tortuguero, fly into the small airport or take a 2 hours boat ride up the Rio Tortuguero, an adventure in itself as the skillful boat pilots navigate the shallow waters, snags and sandbars. Lodges in Tortuguero can arrange for your transportation, as well as accommodations in Tortuguero.
Cahuita National Park - Very uncrowded, Cahuita National Park has 14km of beaches with mangroves and a protected coral reef. Plenty of wildlife here, from shore birds to toucans, macaws, howler monkeys, and iguanas.
Tip: On the Caribbean coast, it's warm and humid. Even in the dry season, it rains. Bring a light rain poncho or jacket, water shoes or sandals, and mosquito repellent and sun screen for kids. A waterproof camera is also handy.