«The Learning in Depth» idea has been proposed by educational theorist Kieran Egan. It is based on the recognition that engaging students imaginations presupposes a significant amount of knowledge. Even though a simple idea, it has nonetheless the potential to transform education, in the sense that students will have the opportunity to develop in-depth knowledge about a topic, and, at the same time, inquiry skills and their creative imagination. This paper provides a brief description of the «Learning in Depth» (LiD) proposal, and then proceeds to the task of putting it in the science education context by discussing the problem of content selection and the problem of evaluating the results of its implementation.