Initially, I teach this when finding prime factorization of numbers. Here is a foldable for their interactive notebooks. I needed to review divisibility rules with my kids before this lesson.
I love prime factorization because it helps the kids review their multiplication tables with smaller numbers. They should know them but so many of my kids don't. :(
I like how this method doesn't take up as much space as the factor trees do.
I have started making more of my notes fill in the blanks. It saves so much time. However, I don't like to have them all written for them.
I do a quick review of short division with the kids. Many of them have never seen this before.
We use this method again when simplifying algebraic fractions.
Before we do upside down division with fractions, we have written fractions in expanded form and simplified to find the answer. They are familar with the exponent rules already.
Next I use this with Greatest Common Factor and Least Common Multiple.
I originally had this foldable as one foldable, but I decided to cut it in half and have a separate page for GCF and LCM. The students have already learned the other two methods for finding GCF. They have also covered exponent rules
Instead of circling the common factors, the students place a large G over the numbers. It is an added visual for the kids.
Upside Down Division for LCM is also called the Ladder Method. I never knew that until I started writing this post. You learn something everyday:)
On LCM the students draw a large L around the numbers as an added visual.
My Pre-Algebra students always have difficulty with this topic. Using the Upside Down Division makes it so much easier for them to understand.
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I am so happy to have all of this written and saved in one place. I litterally had to search everywhere to consolidate all the pieces. I hope there is something new for you to use.
Til next time,