Single-Subject Designs in Character Education: Methods for Rigorous, Contextual, and Practitioner-Led Research

Character education research is often constrained by blunt methodological tools. Surveys capture breadth without depth; case studies offer richness but lack replicability; and randomised controlled trials (RCTs), though indispensable at the policy level, are costly, disruptive, and ill-suited to everyday practice. More troublingly, they rest on an ergodic fallacy: assuming that what works on average must work for each individual. In reality, interventions that deliver modest positive effect sizes typically conceal a mix of no effects, negative effects, and only some benefits. This leaves teachers, mentors, and coaches without rigorous tools to evaluate what matters most: whether an intervention works here, now, for this pupil. This paper argues that single-subject designs (SSDs) offer a neglected but transformative solution. SSDs involve repeated measurement in which individuals serve as their own controls, allowing strong causal inference through replication while remaining sensitive to idiosyncratic development. They democratise research by enabling practitioners to capture and publish the wisdom of context-sensitive practice without the machinery of large trials. Through worked examples drawn from moral and character education, this tutorial demonstrates how to design, measure, analyse, and report SSDs to rigorous standards. SSDs can reshape the field into a cumulative, idionomic science that empowers practitioners and complements large-scale studies.