Simple Addition and Subtraction A different Perspective
Step 1: You can introduce this as a puzzle activity in class and break the class into pairs so that they can brainstorm the puzzles you will be giving to them
Step 2: begin writing on the blackboard following sum
2+5= ?
Let the kids answer the question
2+5=7 (ans)
Rewrite the same sum again:
2+ ?= 7
Now again ask children what wud be the answer for this
They wud obviously say it aloud- 5
The catch is you need to ask them why did they arrive at 5 as the answer- in case they are unable to answer then you need to give a fresh question
Now give them a situation where numbers become objects
For example: There s a bag n which there are a total of 6 balls
As symbols write on the Blackboard-
? balls+? balls= 6 balls
Now tell them you took out two balls from the bag. Ask them where will you put the number ‘2’ on the sum written above
2 balls +? balls= 6 balls
Now ask them the next question- How many balls are left in the bag?
Answer from the children will be 4balls
2 balls +4 balls= 6 balls
Brainstorming question: What did you do to get the answer 4?
and Why did you do that operation?
Explain the logic: Now rewrite the statement as:
2balls + ?balls = 6balls
So to find out how many are left in the bag, we can minus
? balls= 6 balls -2balls
NOTE: The emphasis has to be on the word ‘took out’ that means we are using the operation subtracting
Now give them another example with a bigger numbers
Eg: 15 balls+ ?balls =2 7balls
Give them five mins to discuss n come out with a solution. In case they are not able to get the right answer then you can go ahead explaining the logic again
- Give them more simple sums to solve using addition sign. Once they are clear with addition sign change the sums with’ -‘ signs
Some complex examples are given below. These can be used as brain teasers and help the children solve
