Apparently, digital drugs:
Where should I begin? First, binaural beats' effectiveness are questionable at best. Brian Dunning already did a Skeptoid podcast about them, if you're interested in more details. It appears that most effects of binaural beats have to do with the expectations of the listener (i.e., the placebo effect). Note that this doesn't necessarily mean that they are harmless. If it were true that these kids' experience is due to the placebo effect, it is still an effect on their consciousness. The theory presented in the video is that users of binaural beats will be more likely to try other, illegal drugs due to their experimentation with binaural beats, which could be harmful, of course.
The problem, though, is that this "theory" is absolute horseshit. Because it's not a theory at all, it's a blind conjecture. There is zero evidence that users of binaural beats are any more likely to try illicit drugs later on. Why people think they can just postulate anything that comes to mind, and present it as the next threat to our children boggles my mind. And now cell phones and iPods are banned from this school, based on ignorance and fear.
Next thing you know, they'll be claiming music and video games are dangerous!