Students in these grades should also develop computational-estimation strategies for situations that call for an estimate and as a tool for judging the reasonableness of solutions. This set of Standards reinforces the dual goals that mathematics learning is both about making sense of mathematical ideas and about acquiring skills and insights to solve problems. Rather, the calculator should support these goals by enhancing and stimulating learning. As a student works on problems involving many or complex computations, the calculator is an efficient computational tool for applying the strategies determined by the student. The calculator serves as a tool for enabling students to focus on the problem-solving process.
Calculators can also provide a means for highlighting mathematical patterns and relationships.
For example, using the calculator to skip-count by tenths or hundredths highlights relationships among decimal numbers. Students at this age should begin to develop good decision-making habits about when it is useful and appropriate to use other computational methods, rather than reach for a calculator. Teachers should create opportunities for these decisions as well as make judgments about when and how calculators can be used to support learning. In these grades teachers should help students learn to work together as part of building a mathematical community of learners. The teacher establishes the model for classroom discussion, making explicit what counts as a convincing mathematical argument.