- Within the range of 0 to 30, to say the number that is 10 less than any given number.
Counting in tens is introduced when children are comfortable with counting in ones and identifying a number that is one more/less than a given number. The reason that tens is taught next is because of the simple pattern that it forms in our decimal number system. Whichever number you start with, and whichever direction you count in, the numbers form a clear pattern which children find easy to identify:
0, 10, 20, 30, 40, 503, 13, 23, 33, 43, 53
78, 68, 58, 48, 38, 2891, 81, 71, 61, 51, 41
Children begin by reciting the multiples of ten from 0 to 50 or even 100 if they have a good grasp of number. They then move on to reciting this backwards. Young children learn to rote count very easily and it is surprising how quickly they pick this up.
When children are able to count forwards and backwards in tens, a 100 square is used to demonstrate the pattern. This pattern can then be used on the 100 square to count forwards and backwards in tens from any number.
The next step is to use their knowledge of counting in tens to perform addition and subtraction. Your child can use the 100 square until they gain more confidence in identifying numbers that are ten more or less than any given number.
In the future this knowledge can be extended to adding and subtracting other multiples of ten, e.g. 20 or 50.