What I concluded, especially I took a few neuroscience courses, after was that the computer/database/memory model is not good to explain school and learning.
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My take:
You don't learn to remember what you learn. You learn to build roads, pretty much literally inside your brain (it constantly rewires).
It's more like unpaved paths before road building: First there is wilderness, then there is a lot of traffic, and increasingly that traffic concentrates on more and more clear paths.
The learning of "stuff" is creating paths. The things - ideas, knowledge, facts - that you learn are like the carts travelling the paths. They may be gone - but the paths remain.
So even after every single thing is forgotten - every single traveler and cart is no longer there - what remains is the paths. The wiring inside your brain changes in the learning process. You may not remember much of what traveled through your brain, what created the paths, but your brain nevertheless remains changed.
Even if you forget every single thing, the way you think and react will have changed forever.
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Using the metric "what I remember from my courses" is the wrong metric. Instead, it should be "how did my way of thinking change".
I took a lot (really a lot) of (mostly university level) courses long after university, in fields unrelated to my career and previous study. That's when I noticed far more clearly than ever before, despite very good success (I was even made TA a few times), the concrete things I was able to recall even just a year later was really small. Then I noticed it's the same with my core field really.
The concrete things we know is actually rather small. I forgot sooooo much. Only things I use regularly are available in a way that I could pass an exam (school or university). Still, I changed quite a bit, but it's all "meta". I now know the path I have to take instead of being lost. Even if I don't understand the concrete items e.g. in a medical paper (e.g. names of some genes or proteins), instead of feeling lost I have a "feeling" what it is about, and I can easily look it up and understand very quickly because I have a framework ready to receive what I read.
Our actual "memory" is pretty small, it's all about the paths. Literally, in the brain.