Within the BiKS-8-18 study (“Educational Processes, Competence Development, and Formation of Educational Decisions in Preschool and School Age”), the academic career of more than three thousand students from primary school up to tertiary education was observed. The longitudinal study design encompasses ten years of data collection on students, teachers and parents using a wide range of instruments. In this article, we summarize research findings on three major research questions. First, we discuss the development of reading comprehension in primary and secondary school, focusing on the exploration individual differences and the Matthew-effect. Second, we present research on students’ academic interests in secondary school and the role of social and dimensional comparisons for the development of individual differences. And third, we illustrate findings on the development of students’ goals at the transition from secondary school to tertiary education. Finally, a comprehensive outlook is provided.