In kindergarten, students are faced with multiple models of addition and subtraction and asked to find sums and differences within 10. My ALL TIME favorite model is the number bond. A “Number Bond” is just a visual representation for part, part, whole and tool for breaking apart and joining numbers.

About the Number Bond

A number bond, often appearing as 3 circles: 2 parts, 1 whole, can look intimidating if unfamiliar with this type of model. I’ve seen many kiddos get confused by the parts vs. the whole when completing a bond – especially when the model uses equal sized circles. In my former district, the model was always given in this format. My first year of teaching kindergarten, I came up with a trick to help my students easily identify the parts and the whole of the number bond to aid with their solving. We called our Number Bond… MR. Number Bond! (this is old image, but hopefully gives you an idea)

Mr. Number Bond is your traditional circle bond, but I placed emphasis on his 2 STRONG ARMS! (the 2 lines coming from the whole) Mr. Bond is so STRONG because HE (the whole) carries the biggest number and holds two parts that are equal to him. Before we ever used this tool, the kids would practice rotating their bond and locate the parts vs. the whole. You can grab a free Mr. Number Bond mat here.

Solving with a Number Bond

Quickly interpreting the given information in a number bond (like the parts from whole) is very helpful in solving and knowing which process (compose/decompose) to use to finding the unknown.

This set is included in the Addition Task Cards: Click Here to View

Composing/ finding sums came very quickly and naturally, students learned that when our “whole” is unknown on our mats (like above) that we needed to add our 2 parts to find it! Like in this example: We were given two parts “3” and “3.” By counting out 3 and 3 students will determine that 6 is unknown whole.

This set is included in the Subtraction Task Cards: Click Here to View

Finding the difference/decomposing was a little more challenging at first – especially if seeing a numeral as the whole. When students are given the whole and a 1 part, they will need to use subtraction to find the unknown part. (This model is visually great for seeing the inverse operation of addition/subtraction)

Using counters, I have my kiddos represent the “whole” ASAP with a visual that’s concrete/moveable. Then, we use the information given to us (our part) and subtract it by removing pieces to solve for the unknown part. Like in this example: Students count out 1:1 the given whole and subtract the given part (6) to find our unknown number of 4.

Get Hands-On with Number Bonds

This learner was ready for higher addition practice in February & playing cards help with easy differentiation! This mat and recording sheet are from the larger Winter Mat Bundle of mixed skills!

After learning number bonds, this model was a constant small group warm-up and ongoing center in our class. Students became EXPERTS using them and solving beyond sums and differences to 10! It’s also a fantastic model to support with solving story problems as well! Here are some additional activities that we used during the year to practice bonds. These game mats are from my different Math Mat Collections that includes number bonds and varied styles of addition and subtraction.

Expo markers or “counters” like matching mini erasers work great for counting out sets and completing the problem! This mat is part of Easter Addition and Subtraction