**Special numbers strategy **

This strategy looks for numbers that make patterns, for example tens or hundreds

(a)

3

5

7

4

6 +

37

54

71

42

69 +

(a) 3 and 7 are ten, 6 and 4 are ten, that’s 20; add the 5, this totals 25

(b) older children could group the tens using a mixture of rounding and compatibility, for example 37 and 42 is about 80 …