Bridge 100 by adding or subtracting a single-digit number

Maths

In this unit pupils will find pairs of number that compose 100. Pupils will position 3-digit numbers on a number line and estimate their position on unmarked number lines. They will compare and order 3 digit numbers. In the future unit pupil will add and subtract two 3-digit numbers using partitioning, adjusting, redistribution and bridging. 

In the prior unit pupils used known facts to find multiples of ten that composed 100  and used known facts to find complements to 100. In this unit pupils will find pairs of number that compose 100. They will position 3-digit numbers on a number line and estimate their position on unmarked number lines. They will compare and order 3 digit numbers.

Bridging 100: counting on and back in 10s, adding/subtracting multiples of 10

What is the missing addend? 96 + {{ }} = 100

What's the most efficient way to partition 7 to complete 99 + 7 = 106?

What addend is missing from the number line representation? 

What is the missing number? 108 − {{ }} = 99

What is the missing addend? 6 + {{ }} = 10

What is the most efficient way to partition 6 to complete the calculation 7 + 6?

Match the base ten representations to the numbers. 

This lesson will soon be taken down.

Bridge 100 by adding or subtracting a single-digit number

Lesson outcome