Sometimes estimates are the only answers possible, such as when contractors bid for jobs, business owners figure margins of profit, or school districts predict the next year's budget. Have students review the list they compiled about when their families do arithmetic. Then talk about when accurate answers or estimates are needed. Also, provide opportunities for children to practice estimating. Or ask students to figure out about how much milk they drink in a week, a month, or a year.
Calculators are basic tools that have their place in the classroom.
Practically everyone today has a calculator. We use them when numbers are too complicated for us to do in our heads. Using a calculator is easier than resorting to paper and pencil, and valuable when we want to be sure we're correct. Calculators should not be viewed as arithmetic crutches, but as useful tools. For example, they're useful for introducing decimals.