When our oldest was in yochien, a common homework exercise was to come up with a word that starts with a specified kana and then draw a picture of it.
The clever little bugger always tried to pick words whose pictures are easy to draw. Once, for は, he came up with はり (needle) and just drew a little line. For た, he chose たね (seed) and drew a little dot. We made him draw the plant sprouting from it.
