Mathematics has been long known to be a complicated subject, requiring an advanced set of skills. Each skill learned in mathematics requires different level of effort and goes through a different path of processing when working memory is utilized. Being a leading indicator of children's academic achievement, mathematical cognition is of vital importance and is monitored from a young age, where low performance could be a sign of a learning disability that needs to be addressed. A scoping review of literature was conducted to investigate the fortifying evidence on the importance of working memory in children's mathematical performance, and present the common measures for which future research in this field would need to account. One of the main findings of this research is the strong contribution of working memory to problem solving, whether it is a single-or multi-digit arithmetic in consideration. Verbal working memory will have greater contribution for orally presented problems in contrast to written ones that would interact with visual-spatial sketchpad. A number of measures were agreed on to be good contributors for working memory performance, however some limitations apply on the modeling of working memory which was found to be alleviating some implications; at the same time, providing rich soil for cultivating new research.