As the Clarence B. Robinson Professor at George Mason University, Hazen developed innovative courses to promote scientific literacy in both scientists and non-scientists. With physicist James Trefil, he developed a course that they described as "science appreciation", aimed at non-scientists. It was organized around a total of 20 "Great Ideas of Science" that were later reduced to 18. In addition to writing about their ideas in several magazines, they turned the course into a book, Science Matters: Achieving Scientific Literacy. They used the principles to organize explanations of a "vast number of socially significant, fundamental, or environmentally crucial topics." This was published with an amount of advance publicity that was unusual for a popular science book, including an article they wrote for the New York Times Sunday Magazine, praise from prolific author Isaac Asimov and physics Nobelist Leon Lederman, and a publicity tour. For an article in Science about the book, they provided the author with the original list of 20 ideas and invited readers to send in their comments. About 200 readers responded, generally supporting the idea of such a list while vehemently criticizing many of the particulars, including an informal style and sometimes vague language. Particularly criticized were numbers 1 ("The universe is regular and predictable") and 16 ("Everything on the earth operates in cycles"). Hazen and Trefil argued, in defense of point 1, that it was not intended as a defense of determinism and that they covered unpredictable phenomena like chaos; but they also used the responses to modify the list of ideas in subsequent editions.
Hazen and Trefil went on to write three undergraduate textbooks: The Sciences: An Integrated Approach (1993), The Physical Sciences: An Integrated Approach (1995), and Physics Matters: An Introduction to Conceptual Physics (2004). Hazen used these as the basis for a 60-lecture video and audio course called The Joy of Science.