This paper is the second in a series of Analytical Insights papers, which provide accessible, up-to-date analysis of educational datasets. It is the first in a series that uses the Australian Education Research Organisation (AERO)'s new Longitudinal Literacy and Numeracy in Australia (LLANIA) dataset to explore educational questions. The paper draws on the latest National Assessment Program -- Literacy and Numeracy data to discuss student progress in reading and numeracy. Findings were obtained from AERO's LLANIA dataset, which links individual student results from Year 3 through to Year 9 across Australia. This paper highlights important considerations for supporting students who fall behind in literacy and numeracy -- particularly those who do not achieve expected learning outcomes early in their schooling. Key points: (1) Year 3 students who perform below learning expectations are at a high risk of continuing to perform at that level throughout their schooling; (2) Many students with early low performance do not catch up to their peers, highlighting the need for intervention; (3) Of students with early low performance, the largest movement back onto a pathway of improved performance happens between Year 3 and Year 5; (4) Catching up and staying caught up is not easy to achieve. When students with low Year 3 performance move to achieving expectations in Year 5, only around half continue to perform this way until Year 9. The other half drop back down to below expectations in secondary school; (5) Students from equity groups are overrepresented among those consistently at/below the National Minimum Standards from Year 3 to Year 9 for both reading and numeracy; and (6) It is important that any student learning interventions that are adopted are monitored and assessed for their effectiveness. With additional linkage, AERO's new LLANIA dataset is a tool that can be used to assess the effectiveness of learning support programs. [AERO acknowledges that this publication was made possible by the joint funding it receives from Commonwealth, state and territory governments.]