Life on Other Planets?

Today I discovered that the best place for me to think of blog ideas is my swing-set. I was sitting there, being blinded by the sun (which, by the way, decided to come out today). Spring must be coming! Anyways, like I said; I was being blinded by the sun and it got me thinking about other planets.
Ever since I was a little kid I wondered why we haven’t established some housing on a different planet. Obviously, we need oxygen to breathe to live, and I assumed scientists knew how to make oxygen. It’s like, trees and stuff, right? I’m not sure, this is why I don’t like science (aka, I don’t get it). So, I figured, can’t they make a different planet liveable? Probably expensive and hard to do, but is it possible?
Most likely not, huh? Otherwise they would have done all this by now. I don’t know, I just think it would be cool to live on the moon or something!
Don’t you?