MD.6.0. Knowledge of Number Relationships and Computation/Arithmetic: Students will describe, represent, or apply numbers or their relationships or will estimate or compute using mental strategies, paper/pencil, or technology.
6.C.2. Number Computation: Estimation.
6.C.2.a. Determine the reasonableness of sums and differences.
MD.7.0. Processes of Mathematics: Students demonstrate the processes of mathematics by making connections and applying reasoning to solve problems and to communicate their findings.
7.C.1. Communications: Present mathematical ideas using words, symbols, visual displays, or technology
7.C.1.a. Use multiple representations to express concepts or solutions
7.C.1.d. Express solutions using concrete materials