Shrink notification bar

How do I shrink the notification bar that pops up at the top of the screen? I do not want to get rid of notifications, but I only want to be able to play games and use Safari without accidentally switching apps or interrupting what I'm doing. I want to make the notifications then at the top of the screen taking up no more space then the top status bar with time, battery, etc. I can't find how to do this on my iPad, either.