I'm not sure about the sculpture itself, but it took 22 years to start the first smaller plaster version (1880) to complete the final one (1902).
http://en.wikipedia.org/wiki/The_thinker
you mean on poptropica? well it depends on how good of a gamer you are but it usaly takes a fairly long time. It took me 5 hours but it took my freind 3 days.
if you mean like win the game, then you can't. spore is one of those games that you can never end, like WoW, and stuff like that. if you mean get to space stage, if you play every day, maybe about 3...