Children's strategy use in computational estimation.

Examined strategic aspects of children's performance in computational estimation. 23 5th-grade children (aged 10 yrs old) were asked to provide estimates of 48 3- by 3-digit addition problems. After each problem, Ss were asked to say how they found the solution. Verbal protocols, speed, and accuracy were collected for each problem so as to identify which computational estimation strategy is used on each trial, and how each strategy is used, selected, and executed. The results show that children used 4 strategies: rounding with decomposition, rounding without decomposition, truncation, and compensation. Strategies appeared to differ in frequency and effectiveness. Finally, children chose strategies in an adaptive way so as to obtain fast and accurate performance. Implications of these findings for understanding children's computational estimation performance and strategies in numerical cognition in general are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)