Bonds to 20 and 100

For grown-ups: this lesson in words

Year 2 · Maths

Bonds to 20 and 100: I can find pairs that make 20 and 100.

1. Here are 14 strawberries in two ten frames.

   6 lemons fill the frames up.

   14 + 6 = 20

   Picture: 14 strawberries and 6 lemons in two ten frames. 20 altogether.

2. Your turn: Here are 15 apples. How many more make 20?

   Picture: 15 apples in two ten frames.

   Choose one:

   • 4
   • 5
   • 6

   Answer

   The answer: 5

   5 more fill the frames. 15 + 5 = 20

   Picture: 15 apples and 5 green apples in two ten frames. 20 altogether.

3. Here are 10 rows of 10. That is 100.

   3 rows of 10 and 7 rows of 10.

   3 + 7 = 10, so 30 + 70 = 100

   Picture: An array of 10 rows of 10 counters. A gap splits it after 3 rows, into 3 rows of 10 counters and 7 rows of 10 counters.

Words to know

number bond:

Two numbers that make a total, like 14 and 6 make 20.

tens:

Groups of ten. 3 tens make 30.

bar model:

A bar that shows the whole and its parts.