Mnemonics for practicality

Okay so the other day someone asked me if September had 30 days or not... I responded that "it's the first in the rhyme".

It got me thinking of how many of these mnemonics we have...

Which months of the year have how many days
Thirty days has September, April, June and November.. all the rest have 31. Except, for leap year coming once in four, giving February one day more.

Now I also like the knuckle analogy too...

Screws
Lefty loosey, righty tighty

Acid solution
Water to acid you'll get blasted
Credit to Gerry Bell for that one in year 2 chemistry

Expanding binomial

FOIL... Firsts, outsides, insides, lasts

Crud... Was thinking about this and had a bunch examples and now same remember them..

What can you remember?