Column Addition Of Four Digit Numbers

Objectives

To understand the importance of place value.

To gain confidence with the written column method for addition: to understand that only one column at a time is being worked on and that we work from right to left (smallest place value to largest).

Resources

Abacus 4 Textbook 1 | Squared paper | Expanded Addition Methods - Recap (YouTube)

Today's Lesson

Main Activity

Call out a few random 2 digit numbers and ask your student to divide them by 10, saying the answer as a decimal. You could have your place value column headings written out in front of you if you like, and to start with your student could write the numbers down so they have a visual guide. For example:

45 ÷ 10 = 4.5


10s	1s	.	0.1s
4	5
	4	.	5

Turn to page 60 in Abacus 4 Textbook 1.

Watch Expanded Addition Methods - Recap (YouTube) and the 'Addition' video and look at the examples at the top of the page, with your student.

Assure them that it does not matter how many digits there are in a number, they should not be put off by the numbers having four digits as using the column method means that we only work with one column at a time. Also, even if there are more than two numbers to be added together, only two digits are being worked on at a time, as you go down the column. Remind your student to carry over to the next column, if the answer comes to more than 9 in any column.

Ask your student to copy and complete the calculations on page 60. Encourage them to work independently.

Citations

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