This was a well thought out lesson! Topics were on target with both pre-algebra and algebra standards. The structure of this lesson flowed very well, which would most certainly keep a young student's attention. By keeping the slides very similar throughout, a consistency was provided to the students. On examples, mathematical work was shown toward the left-hand side of the screen and mathematical reasons were shown on the right-hand side of the screen. This consistent structure added to the flow of the lesson.
I think it would be important to ensure that the fact that you must compute the multiplication and division, and addition and subtraction steps from left to right was highlighted. This is a major misconception due to the fact that PEMDAS is often written horizontally rather than vertically.
The video of the PEMDAS rap was cute, but unfortunately very poor in audio quality. I could barely make out the words the singers were saying.