For this standard, students are using concrete models to represent integer operations and also to then connect those models to algorithms. Integers give the increased challenge of working with negative numbers as well, so the most useful tools here would be two-color counters and the use of number lines for certain operations.
For example, if the expression is asking students to subtract -2 from 4, written as 4 – (-2), students should not just memorize rules about positives and negatives. Instead, they could use a number line and look for the distance between the two numbers (which is 6). Students would then connect this back to the algorithm use to solve the expression, and see that subtraction means difference, and we would use that distance to solve.
Jackson drew the following model of a number line to solve an equation.
What equation is Jackson solving?
Adding Integers Using Colored Counters
Adding Integers Using a Number Line
Click on the following links for interactive games.
Click on the following links for more information.
Supporting Standard6.3 Number and operations. The student applies mathematical process standards to represent addition, subtraction, multiplication, and division while solving problems and justifying solutions. The student is expected to:
(C) represent integer operations with concrete models and connect the actions with the models to standardized algorithms