No matter what your age is, it's always hard to try to get over someone you like. But the most effective way is to keep yourself busy and try not to interact with him in order to keep him out of your mind. When you're busy doing something else, your mind is focused on what you're busy with and it won't drift to thinking about him. When you don't see him anymore, then you're also less likely to think of him. It will take time however almost everyone goes through this at some point in their lives so I know that you can too!
