I used basically this algorithm in college with the following setup:

Make a word document that lists all the keys to memorize vertically. Save as PDF

Open the PDF in a viewer with annotation tools. Make a clickable note in the margin just next to each key. Write out the value to memorize in the note field.

Cycle through the clickable notes. When you get one right easily, drag the note more to the left in the margin. As you cycle, focus on the ones furthest to the right. If you get one wrong, move it a bit further to the right.

In general the notes will move to the left until you're comfortable with all of them. And the balancing of which ones you need to see and focus on plays out very naturally and you feel in control the whole time.

There are many downsides with this compared to a tool like anki (e.g. I only used it on a laptop), but there was also something about it that just worked really well for me, so I never ended up switching to a different tool. But this was before anki had the similar algorithm described here. Maybe my experience would be different today

Spaced repetition has been all the rage for 20 years now.

Dozens of apps, thousands of lectures, and it turns out its not really a silver bullet.

There's nothing really wrong with it, it's just that people tend to fall off the same way they do on any other education pattern.

A couple years ago I was thinking "If Google and Apple really cared about kids they would make a spaced repetition unlock system", where by you have to make note cards every week and then have to answer correctly to get into your phone. (obviously requires some bypass system, other rules, etc)

You could probably jury rig it with a popup that comes up after you unlock, but people would never install it anyway.

My personal peeve about Anki: I don’t like its data model. It seems to me that there ought to be collections of notes (which might be things one would download or generate with an LLM or make yourself or share with friends or students). On top of one or more collections of notes are the sets of cards to want to learn, and they can derive from the notes. This includes, roughly, templates plus some concept of which cards are enabled. On top of that is the spaced repetition history and model. There also ought to be a way to constrain what cards should be studied in a given session. (For example, if learning Chinese or Japanese, one might want to have a pencil and paper when practicing writing but not reading. When practicing without paper, one might want to skip the writing cards.)

Anki doesn’t seem to separate these layers at all. Everything is a monolithic database. Import is unpleasant. Export is unpleasant. Sharing is unpleasant. Doing anything other than practicing and editing in the UI is unpleasant. And, every time I try Anki, I get stuck when I can’t manipulate my own data outside Anki.

Is there any system out there that doesn’t have this issue?

Super nice, thank you for this post! Based on this I've updated the vocabulary learning scheduling in DuoBook (https://duobook.co) to FSRS based. We should be up to date with the science based learning :)

If anyone's interested in experimenting with FSRS, we at Open Spaced Repetition provide official packages in Python, Typescript and Rust

PY: https://github.com/open-spaced-repetition/py-fsrs

TS: https://github.com/open-spaced-repetition/ts-fsrs

RS: https://github.com/open-spaced-repetition/fsrs-rs

Currently ts-fsrs and rs-fsrs support FSRS 6 and py-fsrs should also support FSRS 6 in the next day or so. Also, both py-fsrs and fsrs-rs include the ability to optimize the FSRS model from your past reviews!