This teacher guide from Stanford Graduate School of Education’s Classroom-Ready Resources About AI for Teaching (CRAFT) initiative offers a gamified lesson to introduce high school students (grades 9–12) to the ethical concerns of artificial intelligence (AI) use. As the capabilities of AI continue to evolve, there is a greater need to think about its ethical implications. This guide centers students’ personal and cultural backgrounds in informing beliefs about AI and making decisions about what principles should guide its use. It introduces a comprehensive set of prompts called “Ethical Engine Cards” for students to discuss different scenarios as they relate to their own values. For example, the guide raises questions such as whether AI should be allowed to override human decisions, prompting students to examine issues of human agency, responsibility, and machine decision-making. These types of questions are designed to strengthen critical thinking and ethical reasoning. High school educators across content areas may find this resource valuable for guiding thoughtful discussions about the use of AI and its broader ethical implications.