Teaching Resource

Prime and Composite Number Sort

PDF, Google Slides | 7 pages|Grades: 4 - 5

Identify prime and composite numbers by sorting 30 number cards into their proper category.

Understanding why some numbers are classified as prime and why some are composite is an essential math skill.

This concept is a building block for algebraic thinking, creating the foundation your students will need to practice number operations like multiplication and division.

In our Prime and Composite Number Sorting Activity, students will review number cards and categorize them by whether they have only 2 factors or more.

How to Use this Prime and Composite Numbers Game in Your Classroom

This game can be used as an independent or partner practice math center activity, or as a guided teaching resource for your guided small group.

To play, shuffle the playing cards and lay them face down. One by one, flip playing cards over and place them under either the Prime Number or Composite Number category cards.

To make this a 2-player game, shuffle the cards and split the deck equally between the players. Each player then takes turns placing a card under the category board where it belongs.

Get More out of Our Prime and Composite Numbers Game

This resource is way more than a card game! Check out these ideas for how to turn this fun sorting exercise into extra learning opportunities:

Scoot Activity

For a fun warm-up activity, give each student in the class a number card. Post the Prime and Composite Number category cards on opposite walls in your classroom. Without speaking, students must make their way to the wall they think their number goes. Once everyone is in place, have the two groups determine if all of the numbers belong.

Mirror Game

This activity is a spin on the classic “Newlywed Game” and works best with small groups because you’ll need enough dry erase boards and markers for each student. Divide the students into 2 groups, and have them sit down in 2 lines facing each other. Read a number off one of the task cards and give the players 10 seconds to write on their board whether it’s a Prime or Composite Number. On your cue (for example, you say “Ready, Set, Go!”) the students turn their boards around so their partner can see their answer. If both students in a pair have the correct answer, they get 2 points. If one has the correct answer, the team gets 1 point.

Prime and Composite Number Brain Buster

Read a number off one of the task cards and give your students 20 seconds to write down as many factors for the number as they can.

Change the Difficulty Level if Needed

To make this game more of a challenge, have students list the factors of each of the numbers before putting them into their respective categories.

If this game is too challenging for some students, the resource can be scaled down by taking out some of the cards.

Easily Prepare This Resource for Your Students

Print the task cards on cardstock for added durability and longevity. Cut out the task cards and place all pieces in a folder or large envelope.

Before You Download

Use the drop-down icon on the Download button to choose between the PDF or Google Slides version of this resource.  An answer key is also included with this download.

This resource was created by Lauren Blankenship, a teacher in Florida and a Teach Starter Collaborator.

Solidify your students understanding of prime and composite numbers with these more tools to fill your daily math lessons:


  Common Core Curriculum alignment

Teach Starter Publishing
Published by Teach Starter Publishing
We create premium quality, downloadable teaching resources for primary/elementary school teachers that make classrooms buzz!

Comments & Reviews

Write a review to help other teachers and parents like yourself. If you would like to request a change (Changes & Updates) to this resource, or report an error, simply select the corresponding tab above.

Log in or sign up to join the conversation.

Suggest a change

Would you like something changed or customized on this resource? While our team evaluates every suggestion, we can't guarantee that every change will be completed.

You must be logged in to request a change. Sign up now!

Report an Error

You must be logged in to report an error. Sign up now!

If any of our resources do not have 100% accurate American English (en-US), simply click on the 'Report an error' tab above to let us know. We will have the resource updated and ready for you to download in less than 24 hours. Read more...


Are you having trouble downloading or viewing this resource? Please try the following steps:

  1. Check that you are logged in to your account
  2. Check that you have a paid subscription
  3. Check that you have installed Adobe Reader (download here)

If you are still having difficulty, please visit the Teach Starter Help Desk or contact us.

Contact us

More time-saving Math Center Activities resources!

Show more Math Center Activities resources