Worked on the chimple/cuba repository to enhance classroom administration by focusing on data integrity, user interface polish, and avatar consistency. Delivered bulk upload validation using JavaScript and TypeScript, implementing duplicate prevention, robust school ID checks, and student name normalization to reduce data errors and ensure reliable data entry. Improved the chapter page layout with CSS and React, removing unnecessary gaps and refining the chapter listing for a cleaner, more usable interface. Addressed avatar rendering issues to maintain consistency across teacher and student views, stabilizing avatar logic and improving visibility in different modes. These updates collectively improved user experience and data reliability.