Data supporting educational entertainment media as an ineffective method to stimulate students to learn academic concepts outside of the classroom?
If you consider the ability to perform robotic surgery a 'classroom concept', there is this study showing that surgeons who play video games are doing better:

http://archsurg.jamanetwork.com/article.aspx?articleid=399740&amp;resultClick=1

On the other hand, it cites an earlier study that links violent video-game use (for kids) to lower grades:

http://www.sciencedirect.com/science/article/pii/S0140197103000927