This study examines what an emerging educational theory looks like when put into practice in an art classroom. It explores the teaching methodology of a high school art teacher who has utilized concept-based inquiry in the classroom to engage his students in artmaking and analyzes the influence this methodology has had on his adolescent students. Its implementation combined an investigation into the nature of the experience with a mixed-methodology case study. The findings are discussed in relation to the work of researchers in art education and critical thinking. Analysis of the data found that a high school art course designed to involve the prolonged in-depth concept-based, or Big Idea, inquiry influenced the adolescents in terms of their critical thinking, artistic growth, sense of self, and reflective understanding of themselves as artists and of the world.