# Prime Factorization

Discussion in 'Fifth Grade' started by Jeky, Jan 26, 2008.

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Jan 26, 2008

Hello!
Awhile back I remember seeing a post about lessons on prime factorizations so I thought I would share something I did with my students last week. I had them pick a number over 50 to factor, then diagram using construction paper. I had them use red squares for composite numbers, green stars for prime numbers, and then had them write the prime factorization at the bottom. It ended up being a really quick (maybe 45 minutes for the whole class to complete) and interesting activity. We "discovered" as a class that it doesn't matter which factors you pick to begin with' you will always end up with the same prime factorization. Anyways, I took some pics, some of them came out pretty neat!
Right now I am trying to figure out how to use prime factorization in a card game. Any ideas???

3. ### eduk8rEnthusiast

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Jan 26, 2008

What a great idea, I like it a lot. It sort of "concretizes" the concept. We made fir trees with star and circle decorations when we did factorization this year. But I didn't think of making the prime numbers one symbol and the numbers needing factoring as another symbol. I'm definitely going to add that, next time. thanks for posting it.
For the card game, maybe try your own twist on Concentration?

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Jan 26, 2008

Great idea - thanks for sharing, especially the photos!

5. ### noreenkCohort

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Jan 27, 2008

Looks great!

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Jan 28, 2008

Those look really nice! My class did prime factorization just before Christmas, so we decorated trees too, eduk8r. I like this idea too! I bet the kids enjoyed it, mine did!

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Jan 28, 2008

Oooh. Send that in to Mailbox magazine. That's right up their alley!

8. ### mmath1212Rookie

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Feb 1, 2008

That is a wonderful idea. I have been trying to think of something concrete to have my students do in regard to prime factorization. It looks like you had them use straws to connect the numbers?

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Feb 1, 2008

Actually I just had them use white crayon if they had a black background and black marker if they had a colored background.....but using straws could work just as well I'm sure!

10. ### cheeryteacherEnthusiast

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Feb 9, 2008

My kids did prime factorization a few weeks ago. I told them that they were decorating Christmas trees and the prime numbers were the decorations. They had to circle the prime numbers to create the decorations. I will do your idea next year, maybe with smaller stars and squares so they can put the finished product in their interactive notebook.

11. ### PeachynessVirtuoso

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Feb 10, 2008

We did your activity this past week. They really enjoyed it!!! I realized something while we did your activity that I will have to make a note of for next year. Before I have them make their factor tree, I will have them write the whole thing out on their white boards first. A couple of students made some silly mistakes, like one student chose 99 and did 9 x 10. Otherwise, they came out great!!

One student said that he wished we did more things like this.

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Feb 10, 2008

Cool!
I forgot to mention that I had my students draw out a rough draft on paper first, which had to be "approved" by me before they got their materials. I also caught a lot of silly mistakes!