To answer your question directly and bluntly, I'm actually going to say no, the subjectsat school do not prepare a person for real life. Ask any non-teacher adult what he or she remembers from high school history and you will find that it isn't much. The same is true for any subject taught in school that does not directly relate to an adult's career path.
Real life is mostly about being able to problem-solve, make decisions, and learn from mistakes. Yes, schoolitself prepares people for all of these things, but the information learned directly in the subjects taught, in my opinion, are merely tools and avenues for learning how to learn. And, to be even more honest, today's educational system in America, with it's focus on standarized test scores and getting "through" a curriculum, relies much more heavily on memorization of facts than application.
Most high school graduates I know have a very hard time with problem solving and critical thinking. Our education system simply doesn't enforce it nor require it.