this is little about "wa" ^^ http://www.youtube.com/watch?v=iKIK4xNRg4Y "Ga" make the subject stronger than "wa", Taro ga gakko ni ikimashita = Taro is the one who went to school Taro wa gakko ni ikimashita = Taro went to school else they can be very similar to each other ^^ It few time confuse me too, you are not alone ^^ Ganbatte!<3 ^^

Read "Making Sense of Japanese" by Jay Rubin.