Teen staff is very much hit or miss. I've had some of the most amazing people alive as teen staff before (on both CCL and RCI), and I've had some pretty not so great one's as well. Keep in mind that it is you and the rest of the teens that really dictate what happens in terms of activities. For example, on the Liberty, we all decided we would do a toga night, and everyone showed up to the club in sheets. Was that on the teen program? No, but we thought it was a good idea so we did it.
As for the itinerary, it is HIGHLY unique and very much a once-in-a-lifetime experience. Cozumel is Cozumel; don't know if you have been there before, but my experience with it is that there are Mayan ruins (big deal, they are already ruined, but if its your thing, go for it), Chankanaab National Park has some definite appeal to it as well. If you would rather just pay the cab and no entrance fee, there are free public beaches as well that do not charge save the water/other activities (iceberg, canoes, etc...).
Costa Rica has beautiful rain forests. I suggest you see them. The trip out to the forests is often through the country side and is a real eye-opener to the poverty of the country. Oh, and if you get the chance, don't be afraid to stop at a fruit stand and sample the island's fruits (just make sure you keep a bottle of water to wash them off).
Panama is your last stop. The obvious is the Panama Canal, go to the Gatun Locks and take your "textbook canal picture". Beyond the canal, I suggest the Zona Libre in Colon for shopping (duty free; people brought on TVs, stereos, and all sorts of huge things on this stop). I would also suggest venturing to Panama City and experiencing the culture. A handful of quarters on the street go an extremely long way here. Be cautious of the street vendors though, while their stuff is cheap, its also 100% bootleg.
In terms of everything else, I really recommend enjoying your sea days as well. I found those to be most relaxing.
Here's the pics I had from the trip:
http://www.facebook.com/album.php?ai...6&l=64534f7012
Just a note on the pics, (C) 2009 Michael Merali. All Rights Reserved