2
A ten and some ones
Learner’s Book 1: Unit 9, pp. 119–121
GoalShow that a teen number is made of a ten and some ones.
New words
ten · a full ten frame, 10 thingsones · single things, less than 10part-whole · two parts that make a whole
Explanation
Teen numbers are made of a ten and some ones. Look at 13. A full ten frame is 10. Then there are 3 more in the next frame. 10 and 3 make 13, so 13 = 10 + 3. There is a quick way to count: start at 10 for the full frame, then count on the extra dots: 11, 12, 13. A part-whole picture shows the same thing. The whole is the number, and the two parts are the 10 and the ones.
Worked examples
A full ten frame and 7 more. 10 and 7 make 17. 10 + 7 = 17.
The whole is 16. The two parts are 10 and 6. 10 + 6 = 16.
20 is two full tens. 10 + 10 = 20.
Class activity
Ten frame play: draw two ten frames on paper. Put 10 counters, beans or buttons in the first frame. Your partner says a number from 11 to 19. Put the rest in the second frame. Say it like this: ‘10 and … make …’.
Practice
1
What number do the frames show?
19
2
10 + 5 = ?
15
3
What is the whole?
12
4
15 is 10 and how many more?
5