Spelling is the biggest category. I record myself saying a word that I've seen him spell wrong. The answer is the written word.
Many of his old life-memories are saved. A picture of a playground he loved, where we used to live. A frame from a movie he liked. Asking for the name of the hero in a book he loved. Anki makes him recognize these things, which keep his memories of them alive. Often ilicits an "Oh yeah!" nostalgia.
Recognizing countries on the map is not trivial. On the playground, he met a kid from Syria. He asked the boy if he lived closer to Turkey, Iraq, Jordan, or Lebanon. My jaw dropped, but the boy was touched and yelled, "Mom! He knows where it is!" and they became friends (for the day). Other times he'll decide out of the blue that he wants to know more about Azerbaijan or some other country that he only knows by shape.
The rest, he's just really proud to know. A kid at school says the moon is a million miles away. He was proud to know the more accurate distance. He wants to know the actual distance to the beach from our house, instead of just "takes forever".
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