So I know I’m not the first to complain that all the vocab mnemonics for “X things” or “X day” or “X people” are lousy because they make no connection to the number. Ok, I remember coconots. How many coconots was it? 8? 9?
The real tragedy is that there is a kinda well-known way to establish mnemonics for numbered lists:
A popular set of peg-words, easy to remember because they rhyme with the names of the first ten natural numbers, is: one is a bun , two is a shoe , three is a tree , four is a door , five is a hive , six is sticks , seven is heaven , eight is a gate , nine is wine , ten is a hen
For example, an alternate rhyme for 3 would be “me”, which is a natural segue to みっつ. The given mnemonic for みっつ does actually work for this, but they drop the ball for everything else!
You could make a mnemonic about coconut wine for instance, and then you’d have a way to tie in the actual numeral for ここのつ