Recently, the Singapore bar model method has come under the spotlight as a useful tool for developing understanding of and fluency in the operations. Like the array model, it also appears to possess some key advantages:
It represents algebraic situations visually, providing a useful ‘missing link’ between concrete and symbolic representations
It makes the structure of the mathematical situation overt
It links key phases of the problem solving process; interpreting the problem and extracting the mathematics, representing the structure of the problem and plugging the data in, and then recontextualising the mathematics and/or representing it procedurally.