We learned it as “My Very Energetic Mother Just Showed Us Nine Planets”. In our house we’ve started saying, “…Showed Us Nothing” out of respect for Pluto.
kids will remember “Naughty Elephants Splash Water” much better, especially since there’s a mental image to go with it and it’s PG.
Not that they’re called north, east, south, and west- the order they’re in.
(I learned “Never eat scrambled worms.”)
In high school bio, King Philip came over for good soup/ginger snaps.
Streets in mid-Manhattan: Fat Men Pee Less
Fifth, Madison, Park, Lexington
As a kid I was taught this story to help remember how to spell “Wednesday”:
A young man was going to wed his girlfriend. When the preacher asked if he was ready to marry her, he was too nervous to say yes or no, so he mixed them up and said “nes”. And he did this on his wedding day.
Okay, it’s kind of lame when I type it out, but it stuck in my brain in second grade, and still comes back to me every now and then.
I just remembered another one from my childhood. A poem:
“Said why eggs double your fee
Your tea is our kewpie
Oh enamel Kay, Jay
I hate G if he decieves B A”
Takes a little remembering, but now everyone wonders how I can say teh alphabet backwards so quick 
His Noblemen Are Kwite Xtra Rude - noble gases from lightest to heaviest (helium, neon, argon, krypton, xenon, radon)
King Philip Came Over For Good Spaghetti
And to add a couple of other classics: Every Good Boy Deserves Favor [or Fudge] for the notes on the lines of the G-clef; FACE for the notes on the spaces.
“Every Angel Does Good, Besides Eddie.” Guitar strings, standard tuning. Low to high, or top to bottom if you and the guitar are right handed.
I remember both versions (clean and dirty) to make a chart of the characteristics of transistors, altho I don’t recall exactly what all the rows are now. I think I can be forgiven, since I learned this in 1973 and haven’t needed it since that class.
Bob … Eats … Carol’s
Vanilla … Pudding … In
A … Big … Glass
Liking … Mostly … Her
Hot … Meat … Loaf
The first line was Base - Emitter - Collector
Second was Voltage - Power - Current
And the last two were Low - Medium - High, then High - Medium - Low
The dirty version was Bob eats Carol’s virgin pussy in a big garage licking mainly her hot moist loins. It was in the Navy and in '73, women were just starting to take the electronics courses, so they had to clean up the mnemonics. Hence Bad boys race our young girls behind victory garden walls - get started now for resistor bands.
Do electronics classes even teach transistor theory these days? Or vacuum tubes? I remember quite a few units covering vacuum tubes. Now get off my lawn!!!
I learned this one in a Navy Electronics Class , too.
“ELI the ICEman”
“ELI” reminds you that the voltage (E) in an inductor (L) leads the current (I), and “ICE” reminds you that the current (I) in a capacitor (C) leads the voltage (E).
Toronto Girls Can Flirt And Other Quirky Things Canadians Do.
Moh’s scale
A mnemonic to remember the order? North is the top of the map, east is the right. That’s hard enough to remember that it needs a mnemonic?
Anyway: dessert, desert, which one is the last course of dinner? The one with two s’s, because you always want seconds.
Principal, principle, which one runs your school? The one that’s your “pal”.
Re: Kingdom, phylum, class, order, family, genus, species
We learned “Kangaroos play checkers on fuzzy green squares.”
Here’s one I still remember even though what it represents is now pretty much obsolete: (Let’s see if anyone else remembers it:) “Let’s Cook Textured Vegetable Protein”
Streets in the heart of Seattle: “Jesus Christ Made Seattle Under Protest”; Jefferson, James, Cherry, Columbia, Marion, Madison, Spring, Seneca, University, Union, Pike, Pine.
Not exactly a mnemonic aid, but a college teacher once told us that when he told a class that he was tired of students confusing meiosis and mitosis cell division on exams, a student piped up and said “it’s easy: my toes is normal”.
“Every acid dealer gets busted eventually.” I had an old hippie for a guitar teacher.
Kim, please come over for good sex.
I’vbe heard the original as Timid Virgins Make Dull Company. I’ve also heard it reversed as Can Dead Men Vote Twice?.
There’s the mnemonic for the color bands on resistors:
Big Boys Race Our Young Girls But Violet Generally Wins
(Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Gray, White. Note that, except for Black and Brown at the beginning and Gray and White at the end, these are the rainbow colors ROY G BIV, without that annoying INdigo that nobody really knows. )
The risque, extremely non-PC version is
Bad Boys Rape Our Young Girls But Violet Gives Willingly.
One from my grandma, on how to spell “geography”: “George Earl’s oldest girl rode a pig home yesterday.”
HOMES - the great lakes. Huron, Ontario, Michigan, Erie, Superior.
There’s “a rat” in “separate”.
In high school chemistry, we learned about two guys named Gerry and Leo.
That was suppoed to help us remember that a GAIN in ELECTRONS is called REDUCTION (G.E.R.), while a LOSS in ELECTRONS is called OXIDATION (L.E.O.)