Research and probably your own classroom experience says that every five minutes one student stop listening and is only hearing his or her teacher. That is probably why Charlie Brown's teachers sounds the way she does..."Wah, wah, wah, wah,"
It is because of this huge dilemma that I have come up with several ideas on mini brain breaks that you can incorporate with your students either as a reward for good listening skills during your lessons, or as a tool to bring kids back to focus if it appears you have lost too many of them.
It is much better to spend 90% of your time teaching and 10% rewarding students for their attention and participation than to spend only half of your time teaching and the other half redirecting and refocusing students.
I have been a writing and math consultant for the last 13 years, and brain breaks have been a vital tool for managing and motivating students!