Lesson: Mental Subtraction of Numbers up to 10,000 Mathematics • 4th Grade

In this lesson, we will learn how to use different strategies to subtract numbers with up to four digits efficiently.

Lesson Plan

Students will be able to

subtract three- or four-digit numbers from four-digit numbers mentally by counting back,
subtract three- or four-digit numbers from four-digit numbers mentally by breaking the subtrahend apart,
subtract three- or four-digit numbers from four-digit numbers mentally using compensation,
select the most effective mental strategy to subtract a three- or four-digit number from a four-digit number.

Q1:

Natalie wants to calculate . She thinks that if she changes the subtraction to , it will be easier to calculate.

Using Natalie’s method, what is ?

Q2:

Chloe is calculating .

She knows that it is easy to subtract 10s, so she solves the calculation in two steps: and .

Following Chloe’s method, what is ?

Q3:

What is 255 less than 3,565?