Mental Multiplication of Multi-Digit Numbers Ending in Zero

Here's more video of the mental math strategies we're working on this month.  Here, you'll see my helpers putting a box around the zeros so they can focus on the basic fact. I refer to this as putting the zeros in your pocket.  After solving the basic fact, they take the zeros out of their pocket and put them in their answer. 

I apologize that the numbers in the video are a bit difficult to see.  The problems that are being solved are 200 x 40, 500 x 40, 60 x 80, 300 x 800, and 70 x 30.

As I said in the previous post, some students will jot down the numbers in order to give an answer.  With enough practice, some students will be able to look at the problem on a flashcard and give the answer without writing anything down.  Students may use whatever process works for them, in class as well as on quizzs and tests. 

Mental math strategies are tested periodically, but are not timed.

Special thanks to my helpers for demonstrating their math skills on camera.  You know who you are.  :)