No, but some can be quite close at times. Something like FFXII for example, that gives you a ton of freedom and lots of stuff to do. It's close, but not quite a Sandbox because they don't give you the same amount of freedom. It's a similar feel though.
I kind of prefer that style though. It's freedom with structure. --- Math problems are the ultimate trick question. No matter how straight forward and simple they seem, the answer is never what you think it is.