Lesson Plan of Addition up to 100
Subject Mathematics
Grade III
Students` Learning Outcomes
 Add numbers up to 100 using mental calculation strategies.
Information for Teachers
 Mental calculation is a skill that not only helps us to become better at computation, but it also enhances the development of number concepts.
 While teaching the lesson, also consult textbook where and applicable.
Material / Resources
Writing board, chalk/marker, duster, Mathematics textbook
Introduction
 Write the question on the board:
 Call any student to solve it on the board.
 On completion, check the work and correct the mistake if any.
 Tell the students that there is another easier method to solve this question mentally.
 First break up these numbers into ‘tens’ and ‘ones’.
 Write on the board like this:
15 = 1 ten + 5 ones
25 = 2 tens + 5 ones
 Count how many “tens” and “ones” and then add.
 Tell the students that this strategy will help you to add the numbers mentally without solving it on a piece of paper.
 Tell the students that let us practice some more questions using mental calculation.
Development
Activity 1
 Write on the board: add 23 and 12 mentally.
 Ask the students to solve it mentally.
 Collect their feedback and write in on the board like this:
 Write some other questions on the board and ask the students to solve.
 Repeat the procedure to solve the question.
Activity 2
 Write on the board: add 22 and 23 mentally.
 Tell the students that we have another easier method to solve this.
 First observe the numbers.
 We can break the number “23” into 22 and 1 to make calculations simple and easy.
 Write on the board like this:
 Count how many ‘tens’ and ‘ones’ and then add:
 Using this strategy, the two numbers become the same. For example 22 and 22, so that we can calculate easily.
Activity 3
 Write the following questions on the board:

 Add mentally:

 Ask the students to solve these questions using mental calculation.
 (They will not be allowed to use any paper)
 Collect their feedback and then ask to solve the questions on the board.
 Check their strategy to solve the questions.
 Appreciate the students having correct answers.
 Provide guidance to the students having mistaken.
Sum up / Conclusion
 First break up the numbers into ‘tens’ and ‘ones’.
 Count tens and ones and then add.
Assessment
 Ask the students to solve these questions mentally:
 Collect their answers and appreciate them.
Follow up
 You want to buy a notebook having price Rs. 65 and a colour pencil box having price Rs. 34. How much total amount do you need to buy these? (Solve it mentally without using any piece of paper).
 Ask the students to solve the questions given in the textbook.