Ethics and morality, fundamental concepts in human society, are expected to be upheld by individuals and effectively taught by teachers to new generations. This study delves into the perceptions of preservice teachers regarding ethics and good within the framework of an ethics and morality course in education. It also explores the ethical and unethical behaviors these teachers most commonly encounter in their school experiences. Utilizing a qualitative case study methodology, the research provides an in-depth analysis of ethics, the concept of (...) good, ethical and unethical behaviors within the Turkish context. Through thematic analysis of data collected over various weeks, the findings reveal that participants perceive ethics as actions, individuals, and ideas that embody values such as justice, respect, and honesty. Their decision-making is influenced by diverse ethical filters aligned with normative ethical theories. For instance, an act is deemed ethical if it does not limit freedom and harm others, conforms to societal norms, benefits others, adheres to laws and rules, instills a sense of righteousness, and stems from good intentions. Furthermore, the study identifies six key qualities defining the concept of good: evoking happiness, being beneficial, proper, pure, preferred, and encompassing both moral and ethical dimensions. The experiences of ethical and unethical acts among participants predominantly relate to themes of inequality versus justice, harshness versus love, ineffective versus effective teaching, inconsistency versus role model behaviors, undesired versus desired relationships with school stakeholders, and the breach versus balance between professional and private life. Overall, this research highlights significant aspects of how preservice teachers perceive the concepts of ethics and good along with unethical behaviors, offering valuable insights for teacher education. (shrink)