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Subtraction Strategies

Added Sep 15, 2016 •

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This video shows a major component of Common Core. Students need to make sense of what they're doing and avoid routine math steps that cause mathematical confusion.

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okay what we have here is a Go Math book and inside of it Bob's a little freaked out because he saw the standard algorithm rent and we're actually not going to hopefully be using that till the end of 4th grade however we still have a number of texts it will present that in the traditional method so in this case we have 652 - 99 and in this book is you might notice there's not a lot of room to really work with a problem so I would suggest definitely giving this to it's an extra piece of paper to work with why they're working so on the problem we have 652 - 99 now once again traditional you're going to see students wanting you just run to the right and start criss cross applesauce and borrowing regrouping playing with every single digit of the problem all we have to do in a problem such as this is make a little more sense of it and realize that we can manipulate the situation by sliding the scale here I can simply chance 652 to 653 by adding one unit by one unit here I'm going to keep the problem balance my ad a unit down below and 99 becomes 100 and the answer is 550 three and that sure does beat out a lot of scratching and slicing and dicing when we could just make sense of the problem and come to our solution good luck

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Subtraction Strategies

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