Number Sense: Unitizing Principle

Developing Number Sense: Principles of Counting

All concepts of number sense need to be actively taught.

The unitizing principle helps students develop the understanding of place value. This principle of counting is the last to be taught when all of the other principles are understood.

Unitizing Principle

When students have developed the understanding that our math system uses base ten units. Objects are grouped into ten once a number is bigger than 9. And then, into sets of 100 when the number is bigger than 99.

When this occurs, students are aware of the concept that a one appears in the tens column and a zero in the ones column.


Hands on manipulation of objects, especially base ten or snap cube manipulatives, help students learn this concept.

Have students play games together with manipulatives and have them build the numbers to represent their ideas. For instance,"I had 5, but now I have 5 more. What number do I have?" Playing number games like this help children see this principle concretely and helps them to understand it in a deeper way.

Weekly Round-Up: January 20th, 2018

Being back at school has been great!

Between writing report cards and focusing on some home renovations I haven't been able to keep up to date on posting every week. I finally have had some time to share a bit about a variety of different engaging activities we have been up to lately.

1. Letter & Sound Assessment

Upon coming back to school, my first priority for my literacy program was assessing students letter and sound ID. I created a google form to assess student knowledge.

It worked great!

The form automatically collects all the data I need to inform small group instruction and tells me exactly which letters students don't know. The way I designed it, I can label each child by ability groupings! I usually find these assessments to be tedious but I will admit, this was a quick assessment tool! Click on the image below if you want to check it out.

2. Healthy Foods

We have begun to explore the food groups in depth.

In order to expose our students to a variety of possible new fruits, we asked for parents to donate a fruit to make a fruit salad. A variety of donated fruit came in!

We learned about the importance of clean hands and that it is not safe to touch sharp objects - only adults can use them. Students helped wash, peel and place fruit into the bowl once it had been cut by an adult. Whoever wanted to join did, and as a result, they all had a keen interest in trying out our salad.

We didn't eat it immediately as we wanted to put everything in the fridge to make it all cold. The children loved it!

3. 2D Shapes

We have discovered that our students LOVE to play 4 Corners.

We used this set to play this game and every time we have whole group learning the class is begging to play! Students learn their shapes, we count back from ten to find a new shape for those who have not been removed from the game AND students learn to regulate as they MUST walk or they are out of the game.

Click on the photo below to see more about it.

4. Fine Motor

To complement our 2D shapes learning we pulled out some lacing activities. We have a specific time set aside every day where we get one period to work on social skills, focus students or build fine motor skills.

We have been purposefully using this time to focus on learning how to lace.

Can you believe this is done by a student who is one of the youngest JKs in our class!

5. Geometry

Geoboards are engaging ways for students to explore with shapes.

I pulled these out and the first thing an SK from my class last year said, "I love those! I played with those every single day you put those out last year! Thank you for bringing them back to our classroom."

What children enjoy often surprises me. If you look at the image below, these are the complex images and patterns students have been building with them with no prompting.

Shapes, patterning, fine motor and color exploration are all in one activity. I am always amazed at the learning that students demonstrate!

Check out my other Round-Ups here or  Follow me on Bloglovin' to see more ideas for learning activities in kindergarten!

Farmhouse Bucket Labels

I am excited to share with you the new bucket labels that I made for my classroom at the beginning of the school year.

This year has provided a lot of new opportunities for us to be able to be purposeful in planning and designing our classroom. We went for a farmhouse look. We have a grey classroom and we are using tin buckets throughout our class for storage because we have found that plastic bins break to quickly.

In order to bring this calm culture out of the classroom and into our hallway, we added these grey labels to our buckets. It is important to have proper, clear spelling of all children's names which these labels include as well as a photo. Some of the photos are in color and others are in black and white.

Although it is hard to tell, the photo on the top is printed in black and white and the bottom is using my color printer. To be honest, there isn't really much of a difference and I've decided that I'm planning on printing in black and white from now on to keep my classroom budget more affordable!

I love them so much that I decided to make them available to others! If you want to check them out, click on the image below!


Number Sense: Movement is Magnitude

Developing Number Sense: Principles of Counting

All concepts of number sense need to be actively taught.

The one-to-one correspondence principle ensures we accurately count objects one at a time.

Movement is Magnitude Principle

When children understand that when you count in a stable order, each time you count an object it is increasing by one. In contrast, if you are counting backwards, in stable order, each time you are decreasing by one. 

This concept can also be applied to skip counting. So, if you are counting by 2's you know that you are constantly adding or decreasing the number by two.


Building towers with blocks, lego or any type of manipulative that is of a consistent height helps teach kids the visual concept of movement is magnitude.

Graphing with charts is a visual representation where children can see this concept. Especially when the topic is related to their personal lives. For example, how many people walk to school versus how many people take the bus?

For children ready for skip counting, moving manipulatives two at a time while they are counting can help them understand the consistency of this principle.

This number wall is often what I use to represent number sense with my students. At the bottom of the posters, we represent movement is magnitude. We usually use photos of our students, as represented in this pictures above.


Number Sense: Cardinality Principle

Developing Number Sense: Principles of Counting

All concepts of number sense need to be actively taught. Cardinality principle is one of the higher order concepts of number sense that children in kindergarten learn. 

Cardinality Principle

Cardinality is the ability to understand that the last number which was counted when counting a set of objects is a direct representation of the total in that group.

A child who understands this concept will count a set once and not need to count it again. They will automatically remember and know how many are represented.

Students who are still developing this skill need constant repetition of counting and explicit teaching through modelling that they do not need to count over and over again when it will result in the same number. Students who have difficulty with their working memory may have difficulty with this concept.


Simply counting objects that are meaningful to children's lives will help them develop a basic understanding of cardinality. How many candies do you have? How many blocks are in your tower? etc.

Practicing to develop subitizing skills helps students develop cardinality. When children automatically recognize a number they know how many are the set. These two principles are closely related but not the same.

These are some of the activities we use to teach cardinality.

Number Line Fluency
I love this activity as it allows me to choose various representations of numbers based upon what concepts I know students already know. They then need to count the objects in order to know how many are in the set/representation if they don't already know the representation of the number. Then they need to hold that number in their working memory in order to put the numbers in order.

Subitizing Activity
This is a simple tally game. Students flip over a variety of different representations of numbers (sets of bears, tally marks, finger representations etc) and then mark off which number they found. This is a fantastic game to teach cardinality!

Number Puzzles
I place out a variety of different puzzles which represent different numbers and students need to match the numbers to make a puzzle. Students need to count various objects (such as ten frames, fingers, tally marks etc.) and hold that number in their head. 

If they play enough or understand the concept of cardinality, they will hold the number in their memory and it will help them solve the puzzles!

Number Talks
Number Talks are a huge support to develop students ability to understand cardinality.

We use Number Talks on a regular basis in our classroom and it has made huge gains in our students understanding of numbers and has helped to solidify their fluency of numbers.

If you want to check it out there is a link to an Amazon affiliate if you click the image below.

Books to Teach Feelings and Emotions

I love to explore feelings with young children through books and through the arts, such as puppets. 

It is a safe way for children to explore emotions and develop empathy in a safe situation as they realize others feel emotions just like they do.

How Do You Feel?

By: Anthony Browne
This is a simple book for young children which includes a monkey showing a variety of different feelings in relation to simple concepts that children will understand. This is a perfect book to introduce emotions to students.

When the monkey is bored there are no colors to engaged the children. When the monkey is lonely it is very small on the page filled with white empty space.

When the monkey is hungry he has a banana. When the monkey is full there is a picture of a banana peel!

How Are You Peeling? Foods With Moods

By: Saxton Freymann and Joost Elffers
This is a hilarious book for young children to explore feelings using a wide variety of fruits and vegetables. The creators of this book carved unique shaped food, sculpted them with an Exacto knife and then used natural materials like beet juice to add details like mouths to add realistic feelings!

Grumpy Goat

By: Brett Helquist
Goat is the grumpiest animal at Sunny Acres farm until he remembers that there is more the life than eating and being alone.

Tough Guy

By: Keith Negley
This is a perfect book to show that everyone has emotions - even superheroes, ninjas, and wrestlers! They face challenges, frustrations, and concerns no matter how brave, fast or strong they are! 

Get Happy

By: Malachy Doyle
This is a book about opposites. It is a very simple book for very young children to think about what behaviors they can change to help them be happy!

Do Unto Otters: A Book About Manners

By: Laurie Keller
This is a story about Mr. Rabbit. He wonders if he will be able to get along with his new neighbors, who are otters, until he is reminded of the golden rule.

What are your favorite books for teaching emotions to young children?

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