World History: It is essential in today's world to know and understand the world and it's history. When we learn the history of a country and the idea behind their conflicts (i.e. Gaza strip, Middle East) we can understand the ideas, and hopefully try to become part of the solution. Also, the world is where we live! To be able to participate actively in it, we need to be educated about it.
Literature: Literature has been a major part of the world for centuries. Through it we can understand better history/historical events, learn/create new ideas, and just plain old enjoy it. We can also expand our vocabulary significantly be reading.
Language Arts: Language arts is extremely important because it is the study of our language. How can we communicate without learning grammar, being able to spell (although those two seem to be disappearing through texting) and really, being able to speak well.
Geography: Geography is extremely important because it helps to further explain historical events/conflicts, as geographical features (land, lakes, rivers, etc.) have been a source of conflict for millennia. It is also just a good idea to know where things are.