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Did you know that Cicadas base their life on prime numbers? They only hatch at intervals of 13 and 17 years…which are both prime numbers. It is an odd fact, but interesting to note that prime and composite numbers can be found in other areas besides a math classroom. And today we are going to look at these interesting numbers with this set of prime and composite numbers worksheets!

This is a guest post from Rachel at You’ve Got This Math.

What are Prime and Composite Numbers?

When teaching young children what prime and composite numbers are, we tend to focus on one aspect…the number of factors. Though there is much more to prime and composite numbers than this, it is a great place to start.

One way to teach a prime number is that it can only be evenly divided by 1 and itself.

For example, 5 is a prime number. 1 x 5 = 5 and that’s it.

A composite number is a number that has more factors, in addition to just one and itself.

For example, 6 is a composite number: 1 x 6 = 6 and 2 x 3 = 6

Prime and Composite Number Oddities…

It is important to note that some numbers are a little odd.

All even numbers are composite numbers…well except for one number.

The number 2 is a prime number. Why? Because it can only be evenly divided by 1 and itself.

The Number One

Now let’s look at the number 1. We know the rule for being a prime number is being evenly divided by 1 and itself.

Up until the 20th century, many mathematicians would have said that 1 was prime, but now that is changing. In fact, the definition of a prime number now says that a prime number is an integer greater than one that can only be evenly divided by 1 and itself.

One reason is that it does not have two positive divisors.

I also like how Professor Chris Caldwell from Prime Pages explains it:

“Many of the properties of an integer can be traced back to the properties of its prime divisors, allowing us to divide the problem (literally) into smaller problems. The number one is useless in this regard because a = 1.a = 1.1.a = … That is, divisibility by one fails to provide us any information about a.”

What About Zero?

Nope! It’s not prime either.

If you go back to the actual definition of prime numbers, you have to remember that the integer has to be greater than one. Well, that leaves out zero…so zero is not prime.

The definition of a composite number also goes a little further than just having factors other than one and itself. A composite number is a product of prime numbers.

For example, 30 = 1 x 2 x 3 x 5

Since a prime factorization of zero is not possible…zero is neither prime or composite.

Prime and Composite Numbers Worksheets:

Though we may or may not go into that much detail with our students, it is important for them to play around with prime and composite numbers, and this prime and composite numbers worksheet packet allows them to do so.

There are 5 interactive worksheets to make sense or prime and composite numbers.

Prime or Composite Numbers Cut and Paste Pages

The first three pages of the packet are a simple cut and paste activities. The numbers start off small and increase in value through each page.

To complete, kids first, cut out the numbers at the bottom of the page.

Next, they decide if the numbers are prime or composite.

Finally, they glue the numbers under the correct column.

Prime or Composite Writing Activity

The next practice sheet challenges kids to look at the number one, and decide if it’s prime or not. There is a place for them to explain their thinking in words, and then to show their thinking.

See if this doesn’t spark a heated math debate!

Prime or Composite Numbers Problem Solving Challenges

The last practice page has the children solving an area problem using their knowledge of prime and composite numbers.

Once again their is space for the children to draw and model their thinking instead of just writing down the answer.

Enjoy exploring these fun numbers!!

{Click HERE to go to my shop and grab the FREE Prime and Composite Numbers Worksheets!} Looking for more factoring practice fun? Try this activity:

Rachel is a homeschool mom to four little ones, ages 2 to 6. She is a former public elementary teacher, and has recently begun blogging at her page You’ve Got This. You can also find her on Facebook and Pinterest.

The post Prime and Composite Numbers Worksheets: {FREE} Activity Pack appeared first on Math Geek Mama.

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Are you looking for a fun and unique math challenge for your little leprechaun this St. Patrick’s Day? Below you will find a huge collection of St. Patrick’s Day math activities, including hands on ideas, STEM challenges, printables and more!

Hands On St. Patrick’s Day Activities and Games

Students race to create a rainbow and collect gold coins…while practicing fractions! Check out We Are Teachers for game instructions and game card downloads.

Or paint your own rainbows as you explore addition facts to 10!

Use the instructions from The Educators Spin on It to create a St Patrick’s day Sensory Bottle.

Need some fun number sense practice? The Stem Laboratory has printable St Patrick’s Day themed number puzzles.

If you have a love of DIY, you must see these adorable Rainbow Craft Stick Puzzles from Powerful Mothering. Focus on any numbers your student needs.

Looking for some St. Patrick’s Day themed story problems? Teach Junkie have two challenging problems using Lucky Charms cereal. When you’re all done with math, snack is provided! If you want to keep going with the Lucky Charms. Use them for this graphing activity.

Games 4 Learning makes it easy to add some St. Patrick’s Day fun with their free print-and-go games.

St. Patrick’s Day STEM Ideas

Create a Leprechaun trap kit. You gather the supplies, your students bring their creativity. What amazing traps will your students come up with? Instructions found at Little Bins for Little Hands.

Make a rainbow. A crystal rainbow that is. Super simple with magical results. The finished product can be added to a Leprechaun garden, like a fairy garden but for Leprechauns. Instructions for a crystal rainbow from STEAM Powered Family. A sample Leprechaun garden can be seen at Everyday Best, or use your imagination!

Learn about density with this Colorful Rainbow Density Experiment from Schooling a Monkey.

Students are asked to be the Leprechaun moving their gold to a safe spot (they engineer) in this Guard the Gold STEM challenge from Feel Good Teaching. There’s even a video to explain materials and set up!

How far can you catapult a marshmallow? Find out in this STEM challenge from Joy in the Works.

As no prep as STEM gets, print out these worksheets and you’re good to go. Students try to break the code in this 3 sheet set from Little Bins for Little Hands.

St. Patrick’s Day Math Worksheets and Printable Packs

Help your kindergartner or first grader practice important skills with ten frames with this cute printable pack.

Cover many of your early math skills with this free pack from 3 Dinosaurs. Includes math and literacy skills!

Totschooling has a fun printable pack for your under kindergarten crowd.

This huge St Patrick’s Day Pack from Gift of Curiosity has literacy and math skills ages 2-7.

If you have a Montessori homeschool, you must see the activity trays from Living Montessori Now.

St. Patrick’s Day Math for Middle School and Beyond

Can you code a 3 leaf clover? Challenge can be found at Stack Exchange.

Your older child doesn’t have to be left out of the fun. Visit Teaching High School Math for a list of fun activities. The only one that is free is the Reflection, Rotation, Translation–Shamrocks.

How many different ways can you spell shamrock? Find out in this lesson from Math Wire.

Ed Helper has St. Patrick’s Day themed story problems for your upper grades.

Practice solving systems of equations with these cute St. Patrick’s Day mystery picture pages.

And definitely check out these lessons from Yummy Math! One focuses on the “green, green river” in Chicago in celebration of St. Patrick’s Day, and the other is about McDonalds’ “shamrock shake.”

What about you? Do you have any fun or special lessons you pull out for St. Patrick’s Day? Share in the comments!

The post The BEST St. Patrick’s Day Math Activities {All Ages!} appeared first on Math Geek Mama.

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Pi Day is my favorite day of the year to really geek out and try to encourage an excitement about math in my kids. To me, it’s not just an opportunity to learn about circles or the number pi, but a chance to be curious and see how math is all around us. This year we created a fun, yet simple Pi Day art project.

*Please Note: This post contains affiliate links which help support the work of this site. Read our full disclosure here.*

Over the years, I’ve come up with lots of fun ways to celebrate this day with my kids. We’ve sung silly Pi Day songs, and created sweet friendship cards to spread the Pi Day joy.

This year is no exception!

We’re a little early with this project, because the weather was beautiful, warm and not raining for the first time in what feels like weeks. So I jumped at the chance to get outside and create one of a kind math art as we begin to think about Pi Day.

Get Outside: Sidewalk Chalk Pi Day Art Project

The goal of this project was simple: briefly introduce my kids to circles and circle measurements, as well as using a compass, and then let them create unique chalk art.

So before letting them loose, we sat together in the driveway and I explained what a compass is, and how to use it. We talked about what makes a circle a circle, and measuring the diameter and circumference of a circle.

Then I explained that if you take the circumference of a circle and divide it by the diameter, it will equal the number pi. No matter how big or how small your circle.

Yes, I explained all of this to my 7, 8 and 9 year old.

Even though these concepts might normally be taught in middle school or high school Geometry, if kids understand how to measure and divide, they can understand how to find the number pi.

My kids were amazed that this would hold true for any and all circles! I love seeing their amazement and wonder!

Related: Learn what makes a triangle a triangle.

Then I explained their project for the day. The only requirements are that they use the compass to create a variety of overlapping circles. Any size, any quantity.

Then they can color all the different parts in any way they liked.

They loved this idea, and thought immediately of a color by number type of picture.

So yes, the end result will look like a color by number, but without the numbers!

Ready to get started with your own Pi Day art project? Here’s what you need.

Materials Needed for this Pi Day Art Project:
  • Chalk compass*
  • Colored chalk*
  • Black construction paper (if you’d rather do this inside with chalk and paper)
  • Printable lesson (optional, depending on the age of your kids)

*You could also do the same thing with pencil and paper, and color the circles in with colored pencils.

As I said, the weather was beautiful and I was looking for a chance to get outside. So we did this on the driveway with sidewalk chalk.

Alternatively, this would also make a lovely art project using chalk on black construction paper. This is probably what we’ll do on the actual Pi Day, now that my kids are familiar with the compass and the idea of the project.

Once you have all the supplies, kids simply draw various circles. It is a little tricky to use a compass on the driveway and have perfect circles come out. But just encourage kids to do their best. It doesn’t have to be perfect!

After kids are satisfied with their circle design, they can color it in however they’d like.

The result is a beautiful, unique design!

What I loved about this project is that all of my kids were able to participate and learn something, at their own level.

Even my 5 year old was able to learn how to use and practice making circles with the compass!

Now if you want to kick the learning up a notch, you can download the free printable math lesson to go along with this art project.

There are 2 pages included. The first is for younger kids and introduces the vocabulary terms and challenges them to measure the diameter of each of their circles.

The second is a more in depth investigation, in which older kids can discover the number pi on their own.

It includes a table to record the circumference measurements, diameter measurements and the ratio for each of their circles. Hopefully they will notice then that each time the number is close to a pi approximation: 3.14.

Then they take the average of all of their ratios, which will hopefully be an even closer approximation of the number pi.

You can then discuss their findings together as a group.

I hope you enjoy this fun, hands on Pi Day Art Project! If your kids have a fun, unique piece of art to share, tag me on Instagram so I can see it!

Happy Pi Day friends!

{Click HERE to go to my shop and grab the FREE Pi Day Art Project Recording Pages!}

Even MORE Pi Day Ideas:

This post is part of the 28 Days of STEAM series at Left Brain Craft Brain! Check out the full collection of integrated learning ideas here.

The post Simple Pi Day Art Project {Free Printable!} appeared first on Math Geek Mama.

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Looking for some simple practice with addition and subtraction facts to 10? These adorable snowflake pages are the perfect kindergarten winter math challenge!

*Please Note: This post includes affiliate links which help support the work of this site. Read our full disclosure here.*

Providing kids with an opportunity to learn the facts for the numbers within 10 will help them as they begin to move on to larger numbers. Knowing these facts and strategies to solve them helps provide a foundation.

These simple and low-prep coloring pages are so cute, and a really easy way to see lots of different ways to compose and decompose the numbers from 5-10.

Materials Needed for the Winter Addition & Subtraction Pages:
  • Printable worksheets (link to the download at the end of the post)
  • Crayons or colored pencils

And that’s it! Super easy and low-prep!

How to Use the Addition & Subtraction Facts Coloring Pages:

These snowflake coloring pages are pretty self-explanatory, but I’ll explain how to complete them, as well as give you some ideas for extension and discussion.

First, there are 6 pages included in the download, one for each of the numbers from 5-10.

Each page focuses on addition and subtraction facts for a specific number.

For example, on the ‘6’ page, kids have to color all the snowflakes with addition and subtraction solutions equal to 6.

This helps kids see lots of different facts for a single number on one page, helping reinforce the idea that there’s more than one way to get that solution.

It also helps them see different ways to compose or decompose that number, all on one page.

There are several ways you could incorporate this into your lesson as well. You could use these as a whole group activity, with each child working on their own page independently.

Or you could put kids into small groups and give each group a different number to work on.

While this looks like a simple math coloring worksheet, I would encourage you not to give it to kids as merely “extra practice” or “busy work,” but to use it as a springboard for meaningful math discussions.

Extensions and Discussions:

For example, after completing one of the pages, ask students to list the different ways they see to “make 6,” (or whichever number you’ve worked on). See if they can find a pattern!

Then ask what other combinations they can find that aren’t shown on the worksheet.

On the back of their paper, they could try to write out all the different addition and subtraction problems they can think of to make that particular number.

You could then ask if students can create a number sentence with 3 numbers that’s equal to that number (or more!).

What other ideas do you have for extension or discussion? Share in the comments!

And if you like this activity, be sure to check out my set of addition and subtraction mazes. These fun, interactive worksheets challenge kids to learn addition and subtraction facts to 10 as they make their way through each maze.

Buy the Mazes!

And of course, be sure to grab the fun, snowflake addition and subtraction pages! Enjoy!

{Click HERE to go to my shop and grab the FREE Snowflake Addition and Subtraction Facts to 10 Pages!}

Looking for more addition and subtraction resources? Try these:

The post Simple Winter Addition and Subtraction Facts to 10 {FREE} appeared first on Math Geek Mama.

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Looking for the perfect Valentine’s Day math idea for your students? Well, look no further! There’s a huge variety of ideas here for all ages, including math art, hands on activities, Valentine’s Day STEM and printable activities and worksheets. Read on to find an engaging math idea for your kids!

Hands-On Valentine’s Day Math

Visit Math Wire to download instructions on how to make a symmetrical valentine’s day card.

Stay At Home Educator has a free Valentine’s Pattern Block printable to add to your centers or early learning fun. Before handing it to your student, you might challenge them to see if they can make a heart (or how many different ones) out of pattern blocks. Then, compare their hearts to the heart in the printable. Are they the same? What’s different about them.

Mess for Less has a magical art project for you. To add more math to the project:

  • Discuss symmetry (of the heart, of the paper squares)
  • Create symmetry (by putting the same color on the same place in each heart or by only decorating one side and folding it in half to dry). This is called reflective symmetry by the way.
  • Make many little hearts challenging your student to create a pattern (ABAB, ABBA…etc.)

All you need is graph paper and markers for this tessellation activity from Teach Beside Me.

This adorable activity from No Time For Flashcards will have your students counting…for fun! Very customizable. You decide how many hearts go in the jar. You can even have multiple jars, one for each child. To extend the lesson, put something smaller (or larger) in the same size jar (ex: conversation hearts) and start the lesson again. At the estimation stage, ask: “How can we use the answer from yesterday to help us estimate today’s jar?”.

How much is in a handful? Find out with this activity from The Stem Laboratory. All you need is the free printable and some conversation hearts.

Use the free download and conversation hearts (or any manipulative you want) to estimate and measure heart flowers from Buggy and Buddy.

Join Little Bins for Little hands as she shows you 6 simple ways to help your student practice counting in a fun, hands-on way.

If you’re looking for a counting activity that doesn’t use candy, Modern Preschool has your number. Using pom poms and cookie cutters, roll the dice to fill up the cookie cutters. Don’t forget to estimate, either how many pom poms will fit or how many times you’ll have to roll the dice. For older students: have them write down the number sentence as you go.

For a huge list of Montessori-inspired math trays, visit Living Montessori Now.

See how Nature Store sets up their Valentine’s day trays for early learners

Valentine’s Day STEM Challenges

How tall can you build a candy heart tower? Practice engineering, counting, patterns and more with this Candy Heart STEM challenge!

Check out this Cupid’s Arrow Balloon Physics Challenge brought to you by Steam Powered Family.

Follow the instructions from Left Brain Craft Brain to create a Valentine’s Day light up card!

Little Bins for Little Hands has a genius activity making a coded Valentine message using binary. It’s easier than it sounds.

Valentine’s Day Math Worksheets and Printable Packs

Print the free matching activity from Powerful Mothering to practice matching amounts to numbers.

Modern Preschool has a count and clip printable for an easy busy bag or center idea.

All you need is a die and the free printable to do this fun roll and color activity from Fun Learning for Kids.

No other supplies required for this free hundreds chart from I Can Teach My Child.

Practice addition and subtractions with this cute Valentine’s themed printable game from Playdough to Plato.

Use this simple cut and paste activity from Simply Kinder to help students count to 20.

Here’s a 5 page download from Kids Activities.

123 Homeschool For Me also has a fun Valentine’s Day pack for K-4th grade.

You (or your child) will need to cut out the cards. Once that’s done you have a simple grab and go activity for matching equivalent fractions from 3 Dinosaurs.

A Little Pinch of Perfect has a 20 page early literacy and math pack perfect for your pre-k or kinder.

Valentine’s Day Math for Middle School and Beyond

Grab a fun set of Valentine’s Algebra riddle pages here. This includes solving equations as well as order of operations practice.

Looking for something unique and different? These fun logic puzzle challenges will help kids develop logical and critical thinking skills.

From graphing a heart to finding the best deal on candy, Yummy Math has an activity to challenge and intrigue your Middle School to High School aged student.

How many conversation hearts would you need from a bag until you had all of the letters in the word Valentine? Use the instructions from Math Wire and find out!

Looking for a sophisticated math related Valentines card? Math Munch has you covered, with 3 very mathematical cards. Your students will be challenged!

Explore the different types of symmetry with this very well designed lesson from Science Friday. I think most homeschooling parents would find the instructions easy to follow.

Send the ones you love a Math-o-Gram. This interactive program will have your students wondering how. It may even prompt some spontaneous learning.

So I hope you found some fun ideas for your Valentine’s Day Math plans! Share your favorite idea in the comments!

The post 30+ Valentine’s Day Math Ideas for All Ages appeared first on Math Geek Mama.

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Special holidays can be a great time to get out of your normal math routine and let your kids work on something new and different. Logical reasoning is one of those important math areas that is usually lacking in math textbooks. But supplementing your curriculum with the occasional logic puzzle is a great way to weave it in! This set of Valentine’s Day Logic Puzzles is perfect for kids ages 9 and up.

*Please Note: This post contains affiliate links which help support the work of this site. Read our full disclosure here.*

Included in the Valentine’s Day Logic Puzzle Set:

This free printable set includes 3 different puzzles, PLUS answer keys.

The first puzzle is a grid logic puzzle. The goal of this puzzle is to use the clues to match the different groups together.

For example, this puzzle is about friends planning their Valentine’s Day Party:

4 friends are planning a Valentine’s Day party and want all the decorations and food to be red. With the clues below, you must determine which red fruit, red flower, and party decoration each person brought with them.

The grid is then used to mark correct or incorrect answers as you work through the clues.

This helps kids develop and use their logical reasoning skills.

Also included in this download are two sudoku puzzles. If you’re not familiar with sudoku puzzles, they consist of 9 3×3 squares.

You then complete the puzzle by filling it in with the numbers 1-9.

In each row, column and 3×3 square, you can only use the numbers 1-9 once.

So I hope your kids enjoy this fun set of Valentine’s Day Logic Puzzles!

If you’re looking for more logical reasoning resources, check out the links at the end of this post.

{Click HERE to go to my shop and grab the FREE Valentine’s Day Logic Puzzles!} Want more holiday themed puzzles: Try these: And if you have young ones, you may prefer these puzzles, which are hands on, simplified sudoku puzzles: Plus, find even more logical reasoning resources with these fun books for kids:

The post Valentine’s Day Logic Puzzles for Kids {FREE} appeared first on Math Geek Mama.

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There are so many steps to teaching multiplication. It starts with understanding what multiplication is (area or arrays), moves into learning the math facts, and proceeds into conquering two digit and three digit multiplication. There is a step that I often skipped as a classroom teacher: properties of multiplication.

*This is a guest post from Rachel of You’ve Got This Math.

Teaching the Properties of Multiplication:

As a teacher, mastering words like associate property and distributive property sounded hard, and took away from the time needed to learn those multiplication facts!

The more I learn about math, though, and teaching the concepts and not just formulas…the more I realize that the properties of multiplication are important too. Essential, really.

When we teach children the properties of multiplication, we are actually equipping them to solve numerous expressions…and even begin to build a foundation for algebra. Important stuff, right?

So today, I have a few cut and paste multiplication properties pages to help your children learn these important properties.

Preparing the Properties Cut & Paste Pages:

These multiplication properties cut and paste activities are really no prep. Woohoo!

First, print out the pages you need on regular copy paper.

Then provide glue and scissors to your kids and you’re ready to go.

How to Complete the Properties of Multiplication Pages:

Before you pass out these multiplication properties cut and paste pages, it’s important to understand what each word means.

I would also help kids draw or build visual models of each property before working out these cut and paste pages. This will help solidify their understanding and help them to visualize each problem in their mind as they solve them.

Commutative Property of Multiplication

This is probably the easiest of the three properties included in the cut and paste packet.

Just like addition, the answer does not change if you add 5 + 6 or 6 + 5. You can multiply 3 x 4 or 4 x 3 and you will get the answer twelve either way. A simple definition is that order does not matter in multiplication.

In the Cut and Paste packet, there is only one page for this, as this is pretty simple for kids to see and understand. To complete it, kids simply find the multiplication expression that will make the equation true.

For example, the first question is 6 x 4 = ___________.

Therefore, kids must find 4 x 6 as this will make the equation true and models the commutative property.

Associative Property of Multiplication

As we move to our next multiplication property, things get a little more complicated.

We are no longer multiplying two numbers, but instead are multiplying three or more.

But once again, the order does not matter. Or more specifically, where we put the parenthesis does not matter.

Let’s look at the problem 2 x 3 x 4.

I could solve the problem like this:

(2 x 3) x 4

6 x 4


or like this:

2 x (3 x 4)

2 x 12


As you can see, no matter where I put the parenthesis the answer is 24 (or again, the order in which I multiply the numbers doesn’t matter).

There are two cut and paste activity pages for the associative property.

The first one has problems like 4 x 6 = _______. The children then have to find the expression that makes the equation true.

In this case, the answer is 4 x (2 x 3).

There are also some problems that just show the parenthesis switched. Like (8 x 5) x 15 = 8 x (5 x 15).

The second cut and paste activity has kids solving expressions where they could use the associative property to solve.

Distributive Property

Now this is a fun one. Distributive property basically says that you can either multiply the sum of two digits or multiply those two digits separately.

For example, in the problem 5 (3 + 2) I could do two things:

I could multiply five times 3 and then five times 2 and add those quantities together:

5 x 3 + 5 x 2

15 + 10


or I could add up the addends first, and then multiply:

5 (3 + 2)

5 x 5


It’s especially helpful to use an area model to show kids this, with the length of one side of the rectangle equal to five, and the width equal to (2 + 3).

Related: Understanding the distributive property through problem solving (free printable)

There are also two cut and paste activities for the distributive property.

They require that kids once again make the equations true.

They may be asked to find the equivalent expression to 9 (5 + 2) which would be (9 x 5) + (9 x 2).

Sometimes, they may be given (2 x 3) + (2 x 5), which would be an equivalent expression of 2 (3 + 5).

If you’d like more equivalent expression cut and paste pages, try this additional free download!

Enjoy playing with these different properties of multiplication!

You’ve Got This

{Click HERE to go to my shop and get the FREE Properties of Multiplication Cut & Paste Activity!}

Rachel is a homeschool mom to four little ones, ages 2 to 6. She is a former public elementary teacher, and has recently begun blogging at her page You’ve Got This. You can also find her on Facebook and Pinterest.

The post {FREE} Properties of Multiplication Cut & Paste Practice appeared first on Math Geek Mama.

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