How can I stop students from submitting to an assignment without deleting it?

Currently, there isn't a direct "close submissions" button, but here's a workaround:

1. Change the activity's scheduled date to a far-future date (e.g., 1/1/2027).

2. The activity will remain visible on your teacher dashboard.

3. Students will no longer see it or be able to submit work.

Note: We're working on a feature that will allow teachers to control student submissions directly in the future.