Using the 5 and 10 anchor

Using the 5 and 10 anchor is an addition and subtraction strategy. Students decompose both numbers to pull out the 5's or 10's making it easier to add or subtract.

Students split one or both addends to find anchors of five or ten and the leftover amount. Students think about 5s or 10s inside each number, adds them, then adds the leftovers.

Using the five anchor

Using the 5 anchor is a strategy that involves decomposing numbers to find 5s for easier calculations. For example,

6 + 7 = (5 +1) + (5 + 2)

Some important considerations

Using the 5 or 10 anchor is a foundational skill that helps students see how numbers relate to each other. When students focus on number relationships and build an understanding of numbers, they are able to see smaller numbers inside of larger numbers. 

The numbers 5 and 10 provide the strongest benchmarks for thinking about all other numbers.

Students need multiple opportunities to work with ten-frames. Hands-on manipulation of the numbers will help build the understanding that numbers are flexible.

The recognition of the relationship of all other single-digit numbers to 5, at first, and then to 5 and to 10 helps students to structure their understanding of numbers around anchors of 5 and 10.

Using visual models, such as ten frames when introducing basic facts will help students to see that numbers live inside a number.  

Knowing how numbers relate to each other will be helpful for students when they learn strategies for composing and decomposing numbers.

To encourage students to build the foundational skills of Making 10, use mini lessons such as Make 10 Sequence (Lawson, p. 200) as well as the following games: Steal the Bundle, Go Fish for 10 and Make 10 Concentration (see below).