Lesson Plan: Estimating Sums of Three-Digit Numbers: Compatible Numbers
This lesson plan includes the objectives, prerequisites, and exclusions of the lesson teaching students how to use compatible numbers to estimate the value of sums up to 1,000.
Objectives
Students will be able to
- use compatible numbers to estimate the sum of two- and three-digit numbers,
- use estimates to answer word problems,
- identify multiple ways to estimate a sum,
- identify whether the sum is higher or lower than the estimate.
Prerequisites
Students should already be familiar with
- using rounding to estimate sums.
Exclusions
Students will not cover
- mental addition of two- or three-digit numbers.