Distraction seems to be the first major issue with the presence of social media in schools. Also, I worry a bit about dependency becoming a real problem in the future. Though I don't know anyone who has been diagnosed with a technology addiction or a social media addiction, this may be true because it is so commonplace, not because the addiction is non-existent. 

This kind of addiction and dependency is not hugely problematic but could lead to destructive or compulsive behavior. That's just not healthy.

Cyber-bullying and sex-ting have been two huge issues of concern. Social media communication is very hard to monitor, and the actions happen so very quickly which makes it all very difficult to put effective regulations in place.

I would say that the obvious disadvantage of social media in schools is that students will have a lack of focus on their school work.  From an administrative perspective, if social media is allowed in schools then, to some degree, the schools could be held responsible for cyber-bullying or other issues that take place on social media while the students are in school.

Those statistics truly are a basis for concern - scary, in my opinion. I wonder if part of your first statistic got omitted - they use triple the amount of data that was used when? how?

There is a time and place for everything, including social media. However, I truly believe that the basis of relationships among people still needs to come back to eyeball-to-eyeball in-person coming together physically in the same place at the same time. I'm concerned that too many people (not just teens) are coming to think that they can avoid interacting with people or can take the easy way out of meeting commitments by using electronic contacts instead of old-fashioned but humanistic methods.

The following stats come from this website: http://geniusrecruiter.com/2012/03/01/social-media-stats-for-students-and-colleges/

• Teens age 13-17 now use triple the data usage (320 MB per month)
• The average teen sends 3417 text messages per month (Wow!)
• Voice usage among teens declined from an average of 685 to 572 minutes per month

These stats don't necessarily mean that anything negative is happening, but it does indicate that students are spending more and more time online. Some other stats from this site support the idea that more time is also being spent on social networking.

As a teacher, the only time I think of social networking as negative is when students are ignoring me or the lesson to engage in it.

I would have to say that the disadvantage of social media within schools comes from the inability to "police" all of the activities of students. Once something is put up, it is really hard to be taken back down. Outside of that, I would say that social media use in schools could cause greater divides between students (given the ostracizing which already goes on in person).