First you explain what the dividend, the divisor, and the approximately equals sign are. Then you tell the students that with estimated division you always look for a dividend that is divisible by the divisor. With numbers greater than 1,000 you round to the nearest hundred or thousand. For this, sometimes you also need to round the divisor (for example to the nearest tens number). Both are possible; the only difference is in how accurate the estimate is. Discuss this together with the students. Next you show how estimated division works step by step. After that the students practice by choosing the correct estimated quotient. Then the students are going to estimate division problems on their own. Ask how they rounded the numbers to solve the problem. After that, walk the students through the steps of solving a story problem. Have the students solve the next story problems on their own, and ask how they arrived at their answer.
Check whether the students can estimate division problems by asking the following questions:
- When is it useful to estimate a quotient?
- When is it not useful?