I wonder if the colourful life in Cuba may be wasted on an 11 year old.  If I was 11 again I think I would have learned lots from seeing the Pyramids, the Nile and all the archiological sites that Egypt (probably) has to offer.  Very romantic history, in the sense of Egyptian Mummies, curses of the tombs and all that. Not to mention the general day culture.

I don't know much about Cuba, but would imagine your daughter (as an American citizen) may already know about that country and lives close enough to visit it another time.  i.e. it's nearer to her home than Egypt is! :D