The current longitudinal study set out to investigate the development of working memory and English language skills of 5-6 year old English Language Learners. These English Language Learners are all in their first year of formal schooling and all attend the same school in South Africa. South Africa has a rich linguistic diversity which results in many children undergoing their schooling in a language which is not their L1, where oftentimes this language is English. It is well established that English proficiency and working memory skills are predictors of future academic outcomes. Therefore, it is important to track the typical development of both these factors in order to understand when additional support or intervention should be offered. So as to reveal the trajectory of their development, the participants were assessed on working memory and language tasks three times over the course of one year; at the beginning, the middle and the end of the school year. It was found that the growth trajectories were linear for all tested domains of English. The working memory tasks also showed linear development, apart from the complex visuospatial working memory task which showed nonlinear growth.