Examples of integer operations:

Adding with integer chips
Subtracting with integer chips
multiplying with integer chips where 3x4 means 3 in each group and 4 groups.
Adding on a number line
Subtracting by taking away on a number line
Subtracting by unknown part on a number lines
Multiplying on a number line where 3x4 means 3 in each group and 4 groups.