This week’s set is from the “Ten Minutes a Day: Level 1″ series of eBooks for Grade 2, and covers the topic of counting back 3, up to “10 + 3″, and its turnaround, “3 + 10″.

Counting back is a good strategy for very small numbers (-1, -2, & -3). After that, we want students to use other ways to learn their basic facts.

Counting back 3 involves thinking of the numbers which come before the starting number, skipping two and then saying the next number. For example: 12-3=? : Think “twelve, eleven, ten, nine“.