Adults versus Pre-teens and Teenagers

The title of this post has been my ongoing problems for this month. A group of 10-20 pre-teens and teens have discovered my branch library. They are supposed to attend the local Y afterschool program, but according to them that Y is too ghetto. Instead, they prefer to yell, run, chase each other, and hit each other at the library. It can get so loud, it sounds as if you are outside. When they start misbehaving, one of us (the 3 librarians,) issues a warning. Of course they pay no attention to our warnings. Each evening almost always ends up with their group being asked to leave the library. The first time that I got fed up with them, I gave them the option of sitting at a table and reading a book, or they could leave the library. The whole group chose to leave the library. They returned immediately, and accused me of kicking them out. I repeated that they were given a choice and they chose to leave. They then wanted to argue with me. I kept repeating to them that arguing with me wasn't going to change the options that I had given them. This past Thursday, I kicked them out. They decided to block the foyer of the library. This action caused a disturbance with one of the crazy patrons. He chased them cursing. I had to reprimand him and then speak with the teens. I called the library security. The one officer that is assigned to the 27 branches was all the way on the other side of town. I also sent the local police station captain an email, requesting that the library be added to their beat. Next week, we will only have been open 3 months