# Concept of Subtraction- some strategies

Activity Author

Surekha Waldia

Duration

30 mins- 40mins

Objective: Key Core Life Skill to be developed

a:1:{i:0;s:17:"Critical thinking";}

Objective: Key Learning Domains to be developed

a:3:{i:0;s:8:"Remember";i:1;s:10:"Understand";i:2;s:11:"Application";}

Implemented this in classroom

Yes

Objectives to be achieved

Students will be able to recall backward counting while learning subtraction
Students will be able to calculate two digit subtraction (upto 20)
Students will be able solve word problems

Underlying Concept behind this activity

There are three different strategies which are listed in this activity to help students understand the concept of subtraction

Resources required for conducting the activity

buttons, blackboard, colored chalk, pencil colors, worksheets which students can work on based on these strategies

Class Activity Details

**Strategy 1: Using Manipulatives or objects**

Step 1: Take some colored buttons ( 20 buttons) on a check board.

Step 2: Speak aloud that you are taking away 5 buttons from the 20 kept on the check board.

Step 3: Ask children to do back ward counting starting from 20 and reach the number which is left after removing 5 buttons.

You can apply this technique by calling every child in the class or make groups of 2 and give each group buttons or cards made of chart paper to do this activity.

**Strategy 2: Count Back**

Step 1: You can use a colored chalk for this.

Write a two digit number( ex 12) on the board and ask students to remove the number from it (ex 3)

**12 ◊ ◊ ◊ **

11 10 9

equation will be= 12 -3= 9

*put the bigger number in your head and draw dots to help you count back and find the difference*

Strategy 3: Visualize when solving word problems

Step 1: Ask students to visualize what is given in the word problem. for eaxmple :

Meera had 8 candies. She gave 3 candies to her friend. How many was she left with?

Step1: Meera= **Ο Ο Ο Ο Ο Ο Ο Ο**

Step 2: She GAVE= **Ο Ο Ο**

Step 3: Meera was left with=

equation: 8-3=

Refer to the site for more clarity: https://susanjonesteaching.com/subtraction-activities-first-grade/

Practice worksheets

Images of some of the practice worksheet has been uploaded

Uploaded File

Download File
Brainstorming questions asked in class

Some of the key words which help concept of subtraction clear are= GAVE, ASKED, LEFT, EATEN, TAKE AWAY

Evaluation parameters to assess the understanding of the students

Accurate, Complete, Methodical, Precise, Organized

Impromptu changes made if any during activity, reasons

Any suggestions for other teachers while implementing this activity in classroom.

Some of the key words which help concept of subtraction clear are= GAVE, ASKED, LEFT, EATEN