I made an app called Flexi with my friend @BrandonKirbyson. I will just copy the app description from his post:
Flexi is a web app made with SvelteKit and Supabase designed for a school to manage flex periods and share opportunities with students. It aims to make the process of signing up for flex classes easier for both students and teachers, removing the unnecessary and incredibly time-consuming process currently associated with the current outdated and costly system. It also allows for school-wide announcements and featured flex opportunities to be shared with students. Flexi is still in active development, here is the link: github.com/BrandonKirbyson/Flexi (edited)