Is it normal to still feel like a child....?

Even though your in college? I'm 19 and I still feel like a kid, I'm able to act "mature" for important matters (e.g. handling business transactions). But it seems like all other times I'm joking, pulling pranks on people ( not to serious, I use common sense), or wanting to play games like tag and stuff. So is it wrong I still feel like a kid, and if it is are there any tips on kicking my child side out of my psyche?