Hello! It's great that you're exploring different ways for your students to upload their activities. One alternative platform you can consider is using a learning management system (LMS) like Google Classroom, Moodle, or Canvas. These platforms have features that allow students to submit their work securely, and once submitted, they cannot delete or modify the files.
Google Classroom, for example, lets you create assignments where students can upload their work directly to the platform. Once submitted, students can no longer make changes to their submissions unless you allow them to resubmit.
Moodle and Canvas also have similar features where students can upload their assignments securely. These platforms provide a structured environment for managing coursework and submissions.
Using an LMS not only provides a secure way for students to upload their files but also offers additional benefits such as grading tools, communication features, and organization of course materials.
I hope this helps, and good luck in finding the best solution for your students!