Quick Teaching Tip - Multiplying by Multiples of 10

I have a super quick math CGI (Cognitively Guided Instruction) tip to share with you today...

Recently my students were working on multiplying by multiples of 10.  We started off by first discussing what a multiple of 10 was - 10, 20, 30, 40, and so on.  Now, I know there is the way we learned where the teacher taught us to just multiple the two numbers - so in 8x60 - 8x6 and then add 0 to the end - so 48 and 0 would be 480.  While technically this works, it doesn't really show students where the numbers come from and what they represent.

So, I did a quick visual for my kids. We talked about 8 x 60 means you have 8 groups of 60.  So we drew 8 groups of 60 (6 tens sticks for each group) and then counted up by 10s until we got to 480. 


Then, I also showed them that you can use your basic facts to help you. Since you know 8 x 6 =48 then 8 x60 would be 480. So while I do show them the "trick" I also do many examples with the drawing of the place value model so they really see where the numbers are from.  Some of my students who need visuals actually prefer to draw it out.  It helps them to see all of the numbers.  The visual especially works for the kids who are still learning their multiplication facts.

Hope you find this quick tip helpful!

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