Content Area: Math

 

Index: 4.1C Grade 6 CPI 4

 

Standard: 4.1 - Number and Numerical Operations

 

Strand: C - Estimation

 

Cumulative Progress Indicator: 4 - The student will determine whether a given estimate is an overestimate or an underestimate.

 

Grade: 6

 

Sample Activities:

 

·        Students decide, as they discuss each new estimation strategy they learn, whether the strategy is likely to give an overestimate, an underestimate, or neither. For instance, using front-end digits will always give an underestimate; rounding everything up (as one might do to make sure she has enough money to pay for items selected in a grocery store) always gives an overestimate; and ordinary rounding may give either an overestimate or an underestimate.

 

·        Students frequently use guess, check, and revise as a problem solving strategy. With this strategy, the answer to a problem is estimated, then calculations are made using the estimate to see whether this estimate meets the conditions of the problem, and the estimate is then revised upwards or downwards as a result. For example, students are asked to find two consecutive pages in a book the product of whose page numbers is 1260. An initial guess might be 30 and 31, the check might involve concluding that this product is a little over 900, and, as a result, they might revise their estimate upwards.