Romans is Paul's most sustained theological argument — a systematic case for the gospel addressed to a mixed community of Jewish and Gentile Christians in Rome. It covers the problem of human sin, the justice and mercy of God, justification by faith, the work of the Holy Spirit, the relationship between Jews and Gentiles, and practical Christian ethics. For secondary SRE students who are wrestling with big questions about God, morality, and meaning, Romans addresses every one of them.
BibleProject's free Romans overview video (6 min) is essential preparation — it maps the argument of the whole letter before you teach individual sections. Watch it yourself; consider showing it to Year 9–10 students as a unit launcher.