DiaryQuest is a web-based learning management system designed to address challenges in utilizing diary studies in education, particularly in large classroom settings. Diary studies promote student reflection and a deeper understanding of topics like Human-Computer Interaction (HCI), but traditional methods of analyzing diary entries are labor-intensive. DiaryQuest simplifies this process by offering educators tools for creating diary assignments, tracking student submissions, and analyzing entries using methods like Latent Dirichlet Allocation (LDA) and sentiment analysis. For students, it provides an intuitive interface with progress tracking to ensure timely entries. The system also includes interactive visualizations, such as word clouds and dynamic tables, enabling educators to explore student insights more deeply. DiaryQuest enhances the management of diary studies, promotes engagement, and fosters a more personalized and reflective learning experience.