I am interested in "Sage-enabled" textbooks and articles. That is, electronic versions of scholarly documents that incorporate "live" computations with Sage. The Sage Cell Server makes this possible in web pages, while CoCalc offers the advantage of persistent storage and easy annotations. It was the similar potential of the Sage Notebook Server that motivated me to pursue ways to easily author such documents, while also preserving the option of a print or PDF version. This has resulted in the PreTeXt system (née MathBook XML), a project I started four years ago, which has attracted dozens of authors of undergraduate textbooks. I will describe the use of such books in undergraduate courses in linear algebra and abstract algebra, while also demonstrating the types of output PreTeXt can create. Further, I will describe more generally what I see as the key ingredients in Sage's success for undergraduate education, and what more could be done to make Sage even more valuable and useful.