Prime, Composite and Square Numbers

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SWBAT identify prime, composite and square numbers.

Big Idea

Students learn how to think about whole numbers from 1-100 as being prime, composite or square numbers.

Warm up

10 minutes

Warm UP: Count by Sevens!

I like this video to count by sevens because any drill in thinking about adding quickly sharpens minds. Counting by twos and threes are pretty fluent at this point. 5's and 10's are a breeze for them. I don't know about you, but as a kid, I would avoid sevens just because they are hard! I would avoid counting by anything that I really had to think about. So, I think my students aren't much different than me...This video is another fun one! Take a peek at our class having some fun...

Dancin' to Sevens

Core Lesson: Review the Cards

10 minutes

I had my students pair up and take a short walk around the classroom to look at the factor pair cards we had made in a lesson a few days prior.

I asked them to take their notebooks and make a connection to the colors and any other patterns they see with the factor pair cards to review.

Two students had been ill when the factor cards were made, yet they were able to pick out the patterns and notice that prime numbers have one factor pair. Once they were done really looking at the wall of cards, they were asked to share anything they noticed. 

One of my boys raised his hand and said that he noticed that the amount of composite numbers was greater. Another student noticed that even though composite numbers got bigger, the amount of factor pairs they had didn't seem to increase. He said 24 has 4 factor pairs, but 25 has only two. These are the types of conversations that really make me happy. CCSS is helping us build thinkers and "noticers". I am hoping that number sense deepens and that math becomes more comfortable for my students through Common Core.

To help reinforce this idea of prime and composite, my students then logged on to a supportive video resource, Learnzillion.



10 minutes

IXL Math Prime Numbers A.5. I assigned them to work on this for 20 minutes. I instructed them to write factor pairs for any of the answers they got wrong or for the ones they weren't sure of. The object was to be right every time.

Because I have an account with IXL, I can log on and see the progress my students have made a class or as individuals. I had asked my students to write down their work and use their factor pairs to solve the prime and composite numbers.

They really had trouble transferring this assignment to thinking...and not just guessing.

I will have them repeat it and show them that they need to list factor pairs for all of the numbers they don't know for sure are prime or composite. That way, I am assured they are working and thinking.