I created a periodic and spaced repetition plugin for obsidian: GitHub - prncc/obsidian-repeat-plugin: Review notes using periodic or spaced repetition.
The idea is that you can select entire notes to resurface in a “Repeat” view that looks like this:
That particular note uses (exponentially) spaced repetition, but you can have notes repeat every K days/weeks/months/years instead.
The entire state is stored in the note’s frontmatter, and I took care to edit the frontmatter very carefully. In particular, only repeat and due_at fields are ever changed and the reset of the frontmatter is left untouched.
To mark a note as repeating, you could add a repeat frontmatter field manually repeat: every 2 weeks or use one of the provided commands that edit the frontmatter for you. For example, the Repeat this note… command opens a modal that lets you customize repetition to your heart’s content:
The plugin is basically complete. I may add some features like hiding the body of a note until it’s clicked, but I’ve been using this system for about 3 years in various note-taking systems (TiddlyWiki and a custom notes app I made) so I know it’s enough. That is to say, the goal isn’t to replace Anki or flashcard systems.