We believe in practically experiencing everything , not just do paper and pen work.
Today we are learning about addition and subtraction of integers.
And this is what we are using for our learning today stairs leading to our house. 🙂
Introduction to Integers – Using Staircase
On stairs we made a number line representation . Bottom stairs had some negative numbers , followed by zero and some positive numbers. We could do only +4 to -4 as we were limited by number of stairs.
Ms L wrote the numbers using chalk on the stairs.
I let her walk up and down on number line stairs calling out the numbers. It helps master concept that as we move up number value increases and as we go down number value decreases.
Explaining that -4 is less than +2 even though the digit value is more becomes very easy with this method.
The number line explanation consumes 1 or 2 days. So do it patiently and give child some time to master it.
Later we use stairs to perform mathematical operation addition and subtraction on integers.
Integer Addition & Subtraction
Adding two positive integers
I asked Ms L to stand on positive number +2 , add +2 to this , she has to move two stairs up to number +4.
I had my cue cards ready with chalk board paper. To provide little more assistance I wrote a hint instruction “Move up ” or “Move Down” .

Instruction and Hint cards
Explanation:
When you are adding positive number you move up the stairs. When you are subtracting two positive digits you move down the stairs.
We practiced this for a while on positive number line with varied combination.

Adding Positive Integers
Subtracting two positive integers
For now we are just focusing on simple subtraction that is subtracting smaller digit from bigger digit.
Ms L stood stand at +4 position and i asked her to subtract +3 from it. Child will have to come down by three stairs , would be standing at number position +1.

Subtracting Positive Integers
Once again we did multiple combination of subtraction exercise.
Adding two negative integers
Moving to negative number operation should be done in peace as it negate everything that kid has learnt so far because of presence of (-) sign.
Stand on -2 position and add -2 to it , move bottom stairs counting 2 stairs as you go down. After i did it , I asked Ms L to follow me .
Explain that when you add -2 and -2 you are actually increasing the negative number so you will move further down in negative number line.
Little minds have confusion that may sound silly to us, answer those patiently.

Negative Integers

Adding Negative Integers
Again I had my cue cards ready . Just that this time “move down” instruction was for Add operation and “move up” on minus operation.
We are yet to practice negative number addition and mixed integers operation.
Will add one more blog describing in detail steps we used once we are through the exercise.
Do try it and let me know how it went with your child/student.
This needs nothing but stairs and chalk as resources and is very good for introducing number line concept to kids.
Happy learning and happy parenting !
Garima
Lovely concept…