This report provides a comprehensive analysis of developments in schools, classrooms, and the teaching and learning of mathematics and science at primary and post-primary levels in Ireland between 2011 and 2023. Drawing on data from the Trends in International Mathematics and Science Study (TIMSS), collected from students, teachers, and school principals, the report examines trends in school composition, resources, and learning environments. It also explores the organisation and delivery of mathematics and science instruction, assessment practices, instructional challenges, and the integration of digital devices in teaching and learning. These findings are contextualised within national education policies and initiatives, highlighting how Ireland’s education system has adapted to changing pedagogical, technological, and societal expectations. By tracing patterns of continuity and change, the report provides valuable insights into the evolving educational landscape and provides a robust evidence base to inform future policy, practice, and evaluation in mathematics and science education.