For elementary students, developing the ability to calculate mentally helps with understanding basic number concepts and relationships. It improves students ' paper and pencil calculations and eliminates many common errors produced on electronic calculators. Mental calculation is also the cornerstone to all estimation. This mental ability develops the confidence that assures students that they have the skills to quickly solve basic mathematical problems. Students involved in repetitive paper and pencil exercises often become accustomed to following with minimum thought, pre-determined steps.
Mental calculation forces students to think about numbers and number relationships.
Estimation Mathematics is a discipline that we often characterize by its precision in common usage. However, we do not always need, nor are we sometimes able, to attain a high degree of accuracy in our calculations. Approximate numbers are often easier to comprehend and they can also help to develop consistency. When counting, measuring, or calculating it is often advantageous to estimate prior to finding a more exact solution. Development of the concept and skills of estimation helps students to adapt mathematics in a variety of situations.