🧠 15 mnemonics every student should know (from CP to Bac)

Your child rereads their lesson three times, recites it perfectly at night… and the next morning, nothing. Frustrating, right? The good news: it’s not a memory problem, it’s a format. The brain retains abstract lists very poorly, but it loves images, stories, and funny little sentences.

This is where the mnemonic : a very simple trick that turns difficult information into something that sticks by itself. Here are 15 of them, verified and classified from CP (6-7 years old) to Bac (17-18 years old). Some you already know. Others will save your next revision evening.

Why a mnemonic device works so well

Our memory works through associations. A date alone floats in the void; the same date linked to an image, a rhythm, or a joke finally finds a “hook” to attach to. That’s why we know the lyrics of a song heard on the radio by heart without ever having learned them, while we forget a definition reread ten times.

A good mnemonic device does exactly that: it turns the abstract into concrete. It’s not cheating; it’s simply working with the brain’s way.

It’s also the logic of Kidibook adventure notebooks, where each concept is hidden in a story (Plouf’s ocean, Leo’s jungle…): the subscription at €7/month turns the day’s lesson into a mission, and a mission is much easier to remember than an exercise.

Primary school mnemonic devices (CP–CM2, ages 6-11)

1. “But where is Ornicar then?” — the queen of tricks for the 7 coordinating conjunctions: mais, ou, et, donc, or, ni, car. We recite it whenever we need to find them in grammar.

2. The 9 times table on the fingers. Hands flat in front of you, lower the finger of the number to multiply. For 9 × 4, lower the 4th finger: there are 3 fingers to the left (tens) and 6 to the right (units) → 36. It works up to 9 × 10.

3. The planets: “Me Voici Tout Mouillé, Je Suis Une Nouille.” Each word gives the initial of a planet in order: Meercury, Venus, Tarth, Mars, Jupiter, Saturn, Uranus, Neptune.

4. The hungry crocodile (< and >). The sign is a crocodile’s mouth, and it’s greedy: it always opens towards the larger number. In 5 > 3, the mouth is wide open on the side of 5.

5. “m before m, b, p.” Before the letters m, b, and p, we write m instead of n: tomber, impossible, emto lead. (A few exceptions to remember: bonbon, néanmoins.)

6. a / à, et / est, on / ont: the replacement test. Try changing the tense of the verb: if « a » can become « avait » (il a faim → il avait faim), no accent. If « est » becomes « était », it's indeed the verb. Simple and foolproof.

In middle school: the tricks that save tests

7. SOH-CAH-TOA — the star of trigonometry. Ssin = Oopposite / Hhypotenuse, Ccos = Aadjacent / Hhypotenuse, Ttan = Oopposite / Aadjacent. Repeat it like a magic word before each exercise.

8. The order of operations. Always calculate in the same order: first the parentheses, then the exponents, next the multiplications and divisions, finally the additions and subtractions. A little chain to recite before rushing in.

9. The 7 words ending in -ou that take an « x » in the plural. We put them in a sentence: “Come my chou, my bijou, my joujou, on my knees, and throws some pebbles at this owl full of lice. » Seven words, one single memory.

10. The sign rule: “minus times minus equals plus.” Remember it with a friendship image: my friend’s friend is my friend (+ × + = +), and my enemy’s enemy is my friend (− × − = +).

11. Area or perimeter of the circle? They are mixed up all the time. Tip: the perimeter is the boundary (2πR) ; l'area is what you fill, and a surface always has a square unit (πR²).

In high school: memorizing for the Bac (French high school diploma)

12. The derivative of a product: (u·v)' = u'v + uv'. Sing it to a little rhythm: “ u prime v, plus u, v prime ”. Once the rhythm is set, the formula won’t be forgotten during a test.

13. Oxidation or reduction? Two words, two initials: inOxidation, Oyou lose electrons; in Rreduction, there is Rreception of electrons. No more confusing the two in chemistry.

14. Notable values of sine. For 0°, 30°, 45°, 60°, and 90°, sine follows a very regular sequence: √0/2, √1/2, √2/2, √3/2, √4/2. Just count 0, 1, 2, 3, 4 under the root — and for cosine, read the same list backwards.

15. Finding the century of a date. Take the first two digits of the year and add 1: 1789 → 17 + 1 = 18th century ; 2026 → 20 + 1 = 21st century. (Round years like 1900 are exceptions: you stay in the 19th century.)

How to invent your own mnemonics

These 15 tips are just a start: there are hundreds more, almost one for every tough lesson. And the best mnemonic is often the one you create for yourself. The recipe involves three habits:

• Take the initials of what needs to be remembered and make a sentence out of it (like Ornicar).
• Add an image or an emotion : the funnier, more absurd or visual it is, the more it sticks.
• Add rhythm : a sung formula is remembered ten times better than a read formula.

These tips are also a precious weapon when motivation is lacking: discover how make a child who refuses revise without turning every evening into a battle.

Two or three tips are enough to start

A mnemonic device does not replace understanding — but it avoids blockages, restores confidence, and saves a lot of time on homework evenings. Start small: choose two or three from this list, try them this week, and watch the difference on your child's face.

Want to go further? We have gathered hundreds of tips sorted by subject and level in Le Grand Livre des Pense-Bêtes (primary school, middle school and high school, with exercises and solutions). Enough to never hear “I forgot” the night before a test again.