Step 1: We begin the class with drawing pictures of flowers/ balloons or toffees on the blackboard and revise with children the Strike out method.
(7) For example 7 toffee are drawn on the BB.
(2) Teacher strikes out two. Then ask children how many are left.
Step 2: Now tell them we will change the strike out line to a horizontal line and re write the same toffee example as shown below:
To solve this ask children to again strike out 2 from seven toffees. Once you strike off two toffees tell them those cancelled out 2 toffees are the two toffees written after the minus sign
Now make them count the remaining toffees which are left after cutting off two coffees.
Step 3: keep doing this exercise with other examples for children to understand and this time keep asking questions to them like how many number of toffees/ candies/ flowers need to be cut off etc…
When you repeatedly do this exercise children become familiar with the idea of subtraction and understand the new methodology which is being introduced to them.
You can give them practice sheets in class as well as home work to practice this methodology
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