Add two-digit numbers without crossing the tens boundary

Maths

In this unit pupils will learn to find 10 more or less than a 2-digit number. They will  add and subtract 10 to/from a 2-digit number using number facts. In the future unit pupils will add 3 addends, understanding they can be added in any order, bridging through 10.

In the prior unit pupils added and subtracted 1s and 10s from 2 digit numbers. They used number facts to add/subtract a single-digit number to/from a 2-digit number and used a part-part-whole model to represent addition and subtraction. In this unit pupils will learn to find 10 more or less than a 2-digit number. They will  add and subtract 10 to/from a 2-digit number using number facts.

Addition and subtraction of two 2-digit numbers

Match the expressions which will have the same value.

Which expression will have the same sum as 45 + 23?

Which equation will have a sum in the nineties?

Which equation will have a sum greater than 54 + 21 = ?

Use the Base 10 blocks shown to solve the equation

Match the expressions which have the same value.

What is the missing whole in the bar model?

What is the missing addend in the equation? 5 + ___+ 40 + 20 = 67

Which of the digit cards shown would complete the equation?

This lesson will soon be taken down.

Add two-digit numbers without crossing the tens boundary

Lesson outcome