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
Children often get confused and sometimes awed when they they see the numbers written in the form of a sum using symbols which they are not able to relate to their operations in real life . The reason being mechanical way of solving sums from a very early stage . The operation of addition should be related to increase in the given object and subtraction with decrease in the given objects . Similarly = should be understood as the conclusion of the given operation of + or _ . Once they are able to read and understand these symbols as the operation they symbolize the fear of mathematic will turn into excitement . It’s all about the way we are communicating an idea to the child .