In addition to the classical way via the Gymnasium (grammar school), the German school system contains several less known and inadequately researched educational paths that provide access to higher education. Starting with a first lower secondary school leaving certificate, e.g. after attending the Hauptschule or Realschule, further (vocational) paths are nowadays open which conclude with the Abitur or Fachabitur (university entrance diploma). However, previous empirical research has shown that the likelihood of starting a course of tertiary study is clearly correlated with the educational pathways taken at the secondary level and that people who have obtained their qualifications through alternative pathways have significantly less interest in starting tertiary education. Although different theoretical explanations exist, they have not been empirically tested sufficiently. ARTHEE aims to close this research gap and uses data from the National Education Panel Study (NEPS) to investigate educational pathways in lower secondary education. In addition to educational decisions, aspirations, time horizons and performance data also come into focus in order to identify causal mechanisms. The project is divided into three phases: First, it is to be examined whether the availability of alternative educational pathways can reduce social inequality overall. For this purpose, retrospectively collected data of the adult cohort will be used, which contain complete educational pathways. Subsequently, prospective panel data will be used to investigate educational pathways between grades 5 and 9 (phase 2) and from grade 10 (phase 3). The results will help to reassess the role of alternative educational pathways and to better understand educational pathways and decisions in interaction with social background.