This is a longitudinal study that follows the youngest school-age children affected by the COVID-19 pandemic over time to understand the long-term impact of the partial school closure on pupils' attainment (reading and maths) and social skills, and on the gap between the attainment of disadvantaged and non-disadvantaged children. The research, conducted by the National Foundation for Education Research (NFER), builds on findings from a previous study (Rose et al. 2021) and tracks the same pupils who were in KS1 (Y1 & Y2) during the first partial school closure, for a two further years, once in 2021/22 when they were in Year 2 and Year 3 and will again in 2022/23 when they are in Year 3 and Year 4. This report covers the results from the first year of the two-year follow up. Attainment outcomes of pupils in Year 2 and Year 3 in spring 2022, measured by NFER assessments of reading and mathematics, are compared with attainment outcomes for a representative sample of pupils assessed in 2019 and 2017 for Year 2 and Year 3, respectively--before the COVID-19 pandemic. Additionally, the study utilises a repeated measures design such that the reading and mathematics outcomes from pupils in Year 2 and 3 were compared with their outcomes from the previous academic year, when the same pupils were assessed as part of the previous study whilst in Year 1 and Year 2 (Rose et al. 2021). In addition to measuring reading and mathematics attainment, the study also included a teacher measure of pupils' social skills for a sub-sample of twelve pupils within each year group in each school. Contextual information about school practices and any catch-up activities being undertaken with the pupils was also collected though a survey completed by 67 headteachers. [For the previous study, "Impact of School Closures and Subsequent Support Strategies on Attainment and Socio-Emotional Wellbeing in Key Stage 1. Research Report," see ED620409.]