We propose an automatic method for generating educational interactive fiction games using ChatGPT. Our method builds on previous research in narrative generation, aiming for consistency by constructing a complete story flowchart before producing individual scenes. Academic content is integrated into the generated interactive narratives to enhance learning and immersion. User studies including questionnaires and pre-/post-tests were conducted to evaluate the method effectiveness. In trials performed by the authors, the quiz performance showed a negligible change. However, in experiments with external participants, the average number of correct answers increased from 6.5 to 9.0, demonstrating a notable educational impact. The evaluation scores varied depending on the story content and progression, suggesting that structured generation can improve both the learning outcomes and narrative quality.