Explore integer operations using two different balloons and sandbags models. Drag balloons, sandbags, and/or zero pairs onto the board and see how the total result shown on the board changes the models. Nine pre-set integer addition and subtraction problems are given, as well as the ability to create your own problems (option 10). An alert is given when the first term of each expression is formed. (The models can also be used during discussions of multiplication and division, although no problems are included.) This version can show the solution and a solution model for each of the nine pre-set example problems.
