This site has a list of barriers to communication in the classroom: http://edu-helpline.blogspot.com/2014/01/barriers-of-classroom-communication.html. To find good, scholarly sources that relate to those barriers, I would recommend using Google Scholar. A search for "classroom communication barriers" returned more than 300,000 results. Nearly 18,000 of those are from 2010 or newer, so they can provide you with the most current information. Many are available for download or can be viewed online for free.
