Mnemonics are rhymes or phrases used to help remember things. Simple ones are taught to children during early school years, while more difficult examples are used by older students.

Number of days in each month

30 days has September,
April, June, and November.
All the rest have 31,
But February, which has 28 alone
Except in a leap year, that’s the time
When February’s days are 29.

*30 days: April, June, September, November
*31 days: January, March, May, July, August, October, December
*28 or 29 days: February
The colours of the rainbow

Richard Of York Gave Battle in Vain

*red, orange, yellow, green, blue, indigo, violet
The original nine planets

My Very Easy Method: Just Set Up Nine Planets

*Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto
*In 2006, Pluto was removed from the list of planets
Compass points

1. Never Eat Shredded Wheat

*North, East, South, West (clockwise)

2. NEWS

*North, East, West, South
Reading music

1. Every Good Boy Deserves Favour

*E, G, B, D, F: treble clef, on lines, reading from bottom to top

2. FACE

*F, A, C, E: treble clef, in spaces, reading from bottom to top

3. Good Boys Do Fine, Always

*G, B, D, F, A: bass clef, on lines, reading from top to bottom

4. All Cows Eat Grass

*A, C, E, G: bass clef, in space, reading from bottom to top
The Chinese Dynasties

Quit Hanging Suits Tangled, Some Men Mind Quietly

*Qin, Han, Sui, Tang, Song, Mongol, Ming, Qing
*This does not include every sub-dynasty, but rather the broader names. Also note that the Yuan dynasty is the Mongol dynasty.
The British Royal Houses since 1066

No Plan Like Yours To Study Oral History So Wisely

*Norman, Angevin, Plantagenet, Lancaster, York, Tudor, Stuart, Orange, Hanover, Saxe-Coburg, Windsor
*This list is from 1066, when England became one kingdom. It does not include earlier kings, or separate monarchies in Scotland or Wales.
First eight American Presidents

Will A Jolly Man Make A Jolly Visitor?

George Washington, John Quincy Adams, Thomas Jefferson, James Madison, James Monroe, John Quincy Adams, Andrew Jackson, Martin Van Buren
America's Great Lakes, west to east)

Super Man Helps Every One

*Superior, Michigan, Huron, Erie, Ontario
Pi (first 11 digits)

May I have a large container of coffee, cream and sugar?

*3.1415926535
*Number of letters in each word
Mathematical operations, in order)

Please Excuse My Dear Aunt Sally

*parentheses, exponents, multiply, divide, add, subtract
The Seven Coordinating Conjunctions in English

Fanboys

*for, and, nor, but, or, yet, so
Biology classification

Kids Prefer Cheese Over Fried Green Spinach

*kingdom, phylum, class, order, family, genus, species
Roman numerals

I Value Xylophones Like Cows Drink Milk

*I=1, V=5, X=10, L=50, C=100, D=500, M=1000
Spelling rule: i before e

I before E, except after C

*e.g. field, thief, quiet; receive, ceiling, deceit
*This is no longer taught at schools due to the large number of exceptions (eg their, weird)
Spelling rule: dessert

Desert or dessert? The sweet one has two sugars

*dessert is the sweet food, and has two s