In 2016, IBM and Pearson announced a partnership to deliver a next generation learning service in the form of a dialogue-based tutor. Dialogue-based tutoring systems have demonstrated efficacy, but they are difficult to design and scale across domains. We have developed a framework for enabling digital courseware with a dialogue-based tutoring experience that can be applied to new domains with additional domain-specific content, but without re-design of the conversation flow or use case. The framework uses a content model that's consistent across domains, which enables a general dialogue-based tutoring strategy. We identify several challenges to this approach, as well as recommendations for future work.