Background/Context: Despite advances in the learning sciences, a persistent gap remains between research and practice. Purpose/Objective/Research Question/Focus of Study: In this project, we develop and try out a new approach to education research and development in which researchers, designers/developers, and instructors collaborate to continuously improve an online interactive textbook. Intervention/Program/Practice: Using a "learn by doing" strategy, we first created a highly instrumented online textbook for introductory statistics. The design of our online book is based on the practicing-connections hypothesis: Instead of learning individual "bits" of information and then hoping that learners end up with transferable knowledge, we designed a curriculum to engage students in repeated practice of the connections--between core concepts, representations, and the world--that make knowledge transferable. The textbook includes more than 1,200 formative assessments, generating large amounts of data relevant to both the process and outcomes of college students learning of statistics. Using the affordances of technology, we then began working to apply routines and practices from open software development (Git) and improvement science (Toyota Kata) to build an improvement community focused on continuous improvement of the online book. We also are building a technology platform (CourseKata) to publish the book from markdown files stored on GitHub; distribute the book through widely used learning management systems; collect detailed student data and deliver it back to instructors and, in a de-identified form, researchers; and manage experiments that randomly assign different versions of content to different students within a single class, and then assess the effects on students' learning. Research Design: Our research design is a mixed-methods design research and improvement study. We gauge success through measures of process, outcome, and transfer. Conclusions/Recommendations: We are at only the beginning of what we see as a lengthy project. We are encouraged, however, by our progress, and invite others--including researchers, designers/developers, and instructors--to join us in our improvement community focused on improving the transferable learning of basic statistical concepts at scale.