I think you should just do it. Yush, seventh grade is not much different on the dating scene. Although, you might not want to risk what relationship you have. You could go casual, by just bringing up the general subject. Or you could be all like: 'I like you, do you like me?!'
Again, 'dating' doesn't last long in middle school. Besides, it's not the real thing, as say, high school is. The longest I've ever 'dated' a guy was two weeks. If you did 'go out', it wouldn't last long. Just go with your gut!