LESSON PLANNING OF SUBTRACTION OF 3-DIGIT NUMBERS WITH BORROW

Subject Mathematics

Grade 2^{nd}

Student’s` Learning Outcomes

- Subtract ones from 3-digit numbers with borrow.

- Subtract 2-digit numbers from 3-digit numbers with borrow.

- Subtract 3-digit numbers from 3-digit numbers with borrow.

Solve real life problems of subtraction with borrow.

Information for Teachers

- “Minuend” is the name for the number which is being subtracted.

- “Difference” is the word for the number left after the subtrahend is subtracted from the minuend.
- If the unit digit of minuend is smaller than that of subtrahend, for subtraction, we have to borrow from tens digit (one ten = ten units)

- While teaching the lesson, the teacher should also consult textbook at all the steps where and when applicable.

Material / Resources

Writing board, chalk / marker, duster, match sticks, pencils, rubber band, ball frame, blocks of unit tens and hundred, fake notes of different values.

Introduction

- Draw the figure on a chart and display in front of the students.

- As students how many stars will be there if they are combined in the third container? How many blue stars are more than white stars?
- Again refers to the chart paper and tell them that each blue star stands for 10 white stars.
- If 1 blue star goes to the white stars, what will be the number of white stars? (18)
- If 1 more than one blue star goes to white stars, how many white stars are there now? (28)
- Continue till all the blue stars are turned into white stars.
- Explain the process of turning tens into units.

Development

Activity 1

- Tell the following numeral story to the students.
- From ‘10’ units, if we subtracts’ 5 units, how many units will left? (5)
- How many pencils / match sticks that Ali will put into cup board? (115)
- Ten packets of ten pencils make hundred pencils.

Activity 2

- Teacher will ask one student to write 3-digit number on the board. (e.g. 453)
- He will ask another student to show this
- Number on ball frame with beads / balls, such as; Hundreds, tens, unit
- Teacher will say we want to subtract 66 from this number.
- What we will do for subtraction of 66 from this number.
- What we will do for subtraction of 66 from 453? (Will take out 6 balls beads from unit rod, 6 balls from tens rod)
- Are there 6 balls / beads in unit and tens rod? (No)
- Then what we will do? (Will borrow from tens)
- Take out one yellow ball / beads in unit rod in place of yellow one.
- Now there are 13 red ball / beads in unit rod and 4 yellow in tens.

- Similarly we can`t takeout 6 yellow from remaining 4, we will take out one green from hundreds rod and put 10 yellow in tens rod in place of green one.
- Now there are 14 yellow balls / balls in tens rod.
- We can take out 6 balls / beads from 13 and 6 yellow balls from 14.
- How many ball / beads (green) in hundreds rod? (3)
- How many ball / beads of three colors left? (Red =7, yellow =8, green =3)

- What are the remaining ball / beads in all strings? (387)

Activity 3

- Tell the story to the children.
- “In annual sports team A has 612 points. Team B has 424 points. How many more points does team (A) have than (B)?
- Deduce with the help of students.
- To find how many more points team (A) have than B. we will subtract.
- Ask one student to write question on the board.

- Ask another student to subtract units from units by taking borrow from tens.

- Ask third student to subtract tens by taking borrow from hundred.

- Fourth child will subtract the hundreds.

Activity 3

- For how many more points team (A) won?
- Ask from the student to read aloud and write on the board. Team (A) won by 188 point from team (B).

Sum up / Conclusion

- If minuend`s unit digit is smaller than unit digit of subtrahend, we borrow from tens i.e., one ten = ten units.

- The value of left side digit is ten times the digit on the right side.

- There are 10 tens in hundred.
- If minuend digit is smaller than the subtrahend, at any place, then we borrow from the next higher place.

Assessment

- Divide the class into four groups.
- Provide the student cards or fake notes of different amount.

Provide them a paper /worksheet with written story (e.g.

- Ask each group to discuss and solve in their group.
- Ask students to present their work after completion.

Follow up

- You won a prize of Rs. 523 in debate competition; you purchased one colour pencils box costing Rs. 175 for your younger brother. How much money is left? Show the remaining amount you sketching ball frame on the paper and ask them to bring the paper in class next day.

- Ask the students to solve the questions given in their textbook.