The Institute for Tropical Ecology and Conservation (ITEC) has a field station and lab on the beach at Boca del Drago. They've been there for about 10 years, teaching college-level conservation and ecology classes. They have a lab with a library you can visit. There's usually something interesting going on, especially when ITEC's classes are in session - someone may have brought in a plant or animal specimen that is rare or special, or there may be student presentation in progress. You can also ask about arranging a tree-climbing session or a guided forest walk.
You will see tiny crabs, fish, and starfishes in the shallow part of the water... that starfish is heavy!!!
As you make your way to the beach, you will pass through this crooked palm tree. We were goofing off and trying to take some pictures with it, but as you can see, there is a shade covering our faces. Oh well... =)
I must say though, that the beach is a tiny stretch of sand -- and I mean tiny. We had to constantly move according to the tide and to the passing boats... ahahahaha
The water is great though, where it is lighter blue and clear it is shallow, and all of the sudden it turns dark blue, and the bottom drops. We saw a boat stop by with snorkelers -- we wished we had brought our snorkels too!
From Bocas del Toro, you can catch a bus at the town square (next to post office), which has a schedule posted on a wooden board, near the park benches that face the main street. Travel time is around 1 hour approximately; the bus will drive around the main street once, picking up passengers, then once you depart Bocas, it will pick up other passengers along the way.
Going back to Bocas del Toro, check with the bus driver what time the last bus comes around. Sometimes students staying at the lodge there will crowd the entire bus, leaving you to wait for it to come back, or try to catch a ride.. which is more expensive... Oh, and if your bathing suit is wet, don't worry, the bus will give you these brightly colored plastics to sit on, so you don't get the seats wet. =)