Kids today don't seem that bright

As some of you know I am an assistant instructor at a martial arts studio. I am taking over in teaching kids external style and kickboxing. It seems to me that the kids who come to the studio are not very bright. A lot of them seem slow, lacking the basic coordination and cannot comprehend basic instructions or understand biomechanical concepts and theory("are you hands up? which leg in front in a stance?"). Many of them makes the same mistakes dispite being corrected over and over again. Some of them have this black look on their face not knowing whats going on, etc.

I just wonder, what exactly is going on? is it the water, the air and the chemtrails robbing them of their cognitive ability?

My theory is that it is the smartphones, but who knows.  What is certain is that people are becoming morons.