Does he want to go out with me? Signs he's interested?

Well Brenny this is how you get the ball rolling. Mimic everything he does. When he rubs your back place your hand on his knee. Reciprocate every contact he makes with you. Note how far he sits away from you and every time you see him next make sure you sit a little closer, slowly closing the gap between you. These physical gestures say a lot without ever speaking a word. This all works in your favor. You are showing affection without saying it, through body language. If he is interested not only will he reciprocate and get more touchy feely but by the time you slowly close the gap between you, he will be in a position to initiate first contact when it comes to a kiss. Good luck.

If you really like this guy go for it.
Go in for the kill. Haha.
Make sure you flirt.
SIgns he likes you.. Well pretty much body language.
Does he look at you but when you turn towards him he is suddenly looking the other way?
Get one of your friends to watch as you walk by him and then get her to tell you if he watches then you will fer shur KNO!
i hope I helped!