KanjiJLPT N5
Three

Mnemonic

Lay down one wooden plank. Stack one more on top. Then one final plank crowns the pile. Three planks high — you've just built the world's laziest shelf, but hey, it holds your trophies.
Additional thoughts
Each horizontal stroke is the radical One. Three of them stacked = three shelves. Visualize three simple planks floating in midair, perfectly parallel.
Quick recall
Stack one plank, then one, then one more to make three shelves.

Details

The keyword for 三 is three. This kanji represents the number three and is one of the simplest characters in Japanese, consisting of three horizontal strokes stacked on top of each other. Just as one horizontal stroke represents one and two strokes represent two, three strokes naturally convey the concept of three, making it an intuitive and easy-to-remember character.
On'yomi
さん、ぞう
Kun'yomi
み、み.つ、みっ.つ