The dark age of 14

I was nervous before I did my self-introduction with the 3 nensei in Sept. I heard stories about other AETs having problems with the 3 nensei and loving the 1 nensei. Strangely, I can't remember what was said about the 2 nensei. But soon, the 2 nensei left the deepest impression on me.....because I dislike teaching them! In fact, I don't have a problem with the 3 nensei. They're very friendly, earnest, and serious. I'm disregarding the boys that have the look of boredom pasted all over their faces in 3 nensei. The 1 nensei can be rowdy but they're quite genki when learning English. And they are easy to tease. :p BUT....but the 2 nensei are rowdy (in a disrespectful way), bored or hostile in class. The girls are ok but way too quiet. It's as hard to get them to talk as to get the boys to keep quiet. Sometimes I feel so unwanted when I teach the 2 nensei. They are only friendly to me AFTER class, calling out for me outside the corridor. When I'm in the class, they act differently. What's the reason? I don't know. I'll just blame it on the age. It must be tough being 14. That's why they like to make things difficult for me in class.