2
Reading and writing up to 30
Discover Mathematics: Chapter 5
GoalRead and write the numbers from 0 to 30 and use a number to say how many.
New words
zero · none at alldigit · one of the signs 0 to 9tens digit · the first digit, it tells the tensones digit · the last digit, it tells the ones
Explanation
We write numbers with digits. Zero means none: an empty basket has 0 apples. From 10 onwards a number has two digits. The first digit tells how many tens, and the last digit tells how many ones. Look at the ten-frames: one full frame and 7 dots, so 17 is 1 ten and 7 ones. To say how many things there are, count them and write the last number you said.
Worked examples
The bowl has no oranges, so we write 0.
Seif has 1 ten and 4 ones. We write 14.
Rahma counts the roses in her garden: 2 tens and 5 ones. We write 25.
Class activity
Number labels. Write numbers from 0 to 30 on small papers. Hide a pile of small things under a cloth, such as 12 buttons. The child counts them and finds the paper with the right number. Take turns hiding and guessing.
Practice
1
Look at the ten-frames. Write the number.
16
2
How many tens and how many ones are in 28?
2 tens and 8 ones
3
How many apples are in the empty basket?
0
4
Count the birds. Write the number.
26
5
Write in digits: twenty-three.
23