Column Subtraction Or Subtraction With Regrouping

Objectives

To understand column subtraction, recognising the need to regroup numbers, if the bottom digit is greater than the top digit.

To understand and apply the concept of place value.

Resources

Abacus 4 Textbook 1 | Squared paper | Counters or beads | Expanded Subtraction Methods (YouTube)

Today's Lesson

Main Activity

Turn to page 46 in Abacus 4 Textbook 1.

Remind your student of the regrouping process from the last lesson. Ask your student to complete the calculations on the page, using the expanded method of setting out the calculations again. Watch Expanded Subtraction Methods (YouTube) to recap if needed.

Students will often be confused when a zero is used as a ‘placeholder’ in a subtraction calculation like that shown in the example on page 46. Place value counters, such as those shown on the plan in the last lesson, will help to model the regrouping required, if necessary.

Citations

[1] www.youtube.com [2] www.youtube.com