Y2T2 Unit 3 Understanding addition, subtraction and mental calculations

Date of issue: May. 2004

What is it?

Objectives:

Understand that more than two numbers can be added. Begin to add three single-digit numbers mentally (totals up to about 20) or three two-digit numbers with the help of apparatus (totals up to 100).
Use knowledge that addition can be done in any order to do mental calculations more efficiently. For example: put the larger number first and count on in tens or ones; add three numbers by putting the largest number first and/or find a pair totalling 10; partition into ‘5 and a bit’ when adding 6, 7, 8, or 9, then recombine (e.g. 16 + 8 = 15 + 1 + 5 + 3 = 20 + 4 = 24).

Note: The Word file is the Unit Plan only. The PDF file contains the Unit Plan and its associated resources.