Twice a day, our class has been completing Brain Breaks using the YouTube videos that I was able to download. I have to say that this is the highlight of my day. My students get into the dancing with the songs.
Some great Brain Break songs are Sid Shuffle and What Does the Fox Say? To find some great videos, search Brain Breaks and see what comes up. I like that the videos are kid appropriate. It becomes a nice break during the day.
An alternative to the Brain Break videos are Popsicle sticks with activities written on them. For example, one stick may say complete 15 jumping jacks while another one has the students play Simon Says. This was my low tech version until I got the videos. I may still throw them in every once in awhile to help change things up.