Unit: Estimation

This unit includes the explicit teaching of three strategies for estimation: rounding, front-end rounding, and regrouping. It also includes estimating techniques and computations for three digits and values to $1,000. Finally, the unit closes with students judging the reasonableness of their answers. Standards covered: 4.NSO-E.28. Estimate and compute the sum or difference of whole numbers and positive decimals to two places; 4.NSO-E.29. Estimate the answers to calculations involving addition, subtraction, or multiplication; know when approximation or a rounded solution is appropriate and use it to check the reasonableness of answers.; 4.NSO-E.30. Select and use a variety of strategies (e.g., front-end, rounding, and regrouping) to estimate quantities, measures, and the results of whole-number computations up to three-digit whole numbers and amounts of money to $1,000 and to judge the reasonableness of answers.