The Nosara Yoga Institute, whose main business is to offer training to yoga instructors, offers several drop in classes each day for visitors to Nosara. When visiting Nosara for a family member's wedding, I attended four different classes taught by three skilled instructors. Most classes can cater to all levels of students, although some are specifically tailored to beginners. The classes I attended would all be familiar to practitioners of hatha yoga.
The yoga instruction is great, but it is the magnificent surroundings that add the unique aspect to this activity. Yoga platforms in gleaming wood, roofed, but open to the air, are scattered over beautifully maintained grounds. Public classes are taught in the "Treetops" platform or the Belltower (which really does have a bell, and the bats to go with it).
90 minute public classes cost U$10. Mats, blocks and other aids are provided. The facilities are very clean. The serenity and beauty are a nice change from the beach and the dusty roads of Nosara.