Memory techniques that work for school, and the ones that don't

The memory techniques that work for school are, in order: recalling the material before you look at it, spacing those recalls over days, explaining why a fact is true, and pairing words with a drawn image. Mnemonics (acronyms, rhymes, a memory palace) work for ordered lists you must hold exactly, such as the planets or a reaction sequence, and not for understanding. Rereading, highlighting and "memorizing" by staring at a page rank last. Here is the ranking with the evidence, one list memorized and one rule understood as a worked example, and the honest answer to "how do I memorize fast".

First decide: memorize it, or understand it?

Before any technique, sort the material. Some of it is a list you must reproduce exactly: the classes of amino acids, the strands of a course, the sine and cosine values around the unit circle, the stages of cellular respiration in order. Some of it is a rule you must apply: why the derivative of sin x is cos x, how a buffer resists a change in pH, what a competitive inhibitor does to a reaction rate. A list is memorized. A rule is understood, and once understood it is mostly remembered for free.

The common mistake is memorizing a rule you could derive. It costs more effort than deriving it, it breaks the first time the question is asked in a new shape, and it gives you no way to check yourself. The rarer mistake is trying to "understand" a list that has no reason in it. The order of the planets is not a consequence of anything you know; it is a fact to hold, and holding it is what a mnemonic is for.

So: for every item on tonight's list, write M or U beside it. The M items get the techniques in the bottom half of the ranking. The U items get the top half, and a derivation.

The ranking: memorization techniques by the evidence

Dunlosky and colleagues (2013) reviewed ten common study techniques against the research and rated each one's usefulness. Where a technique below was in their ten, the rating is theirs. Where it was not, the evidence column says what supports it.

Technique	What it is	Evidence	Good for
Practice testing (recall)	Produce the answer from memory before you look	High (Dunlosky et al. 2013)	Everything
Spaced practice	Come back to it on later days	High (Dunlosky et al. 2013)	Everything
Elaborative interrogation	Ask "why is this true?" and answer it	Moderate (Dunlosky et al. 2013)	Facts that have reasons
Self-explanation	Explain each step of a procedure or idea to yourself	Moderate (Dunlosky et al. 2013)	Procedures and ideas
Dual coding	A word plus a drawing of it	Supported by Paivio's theory and Mayer's multimedia research; not in Dunlosky's ten	Definitions, structures, processes
Method of loci (memory palace)	Place list items along a route you know	Strong for ordered lists in studies of memory experts (Maguire et al. 2003); not a comprehension method	Long ordered lists
Acronyms and rhymes	A word or line whose letters or beats stand for the items	Not rated in the review; fine for short exact lists	Short ordered lists
Keyword mnemonic	Link a new word to a familiar one by a picture	Low (Dunlosky et al. 2013); useful narrowly	Vocabulary pairs
Imagery for text	Picture a passage as you read it	Low (Dunlosky et al. 2013)	Little
Rereading	Read it again	Low (Dunlosky et al. 2013)	Little
Highlighting	Mark the important lines	Low (Dunlosky et al. 2013)	Little

The ten-technique ranking is the hub's whole subject. The top two rows are the answer to almost every memory question a student asks; the rest of this page is how to run them, when a mnemonic is the right tool, and what to stop doing. The Feynman technique is self-explanation with a structure around it, so it has its own page.

Technique 1: Recall it, then recall it again later

The two top rows are one habit. First, recall: close the notes and write the fact, the list or the definition from memory, then check. Roediger and Karpicke (2006) had students either reread a passage or write down what they remembered of it. A week later, the students who had recalled remembered more than the students who had reread, and the rereaders had been the more confident. Active recall is the method's own page, with five ways to do it and a way to mark yourself.

Second, space it: recall again tomorrow, then in a few days, then in a week. Cepeda and colleagues (2006) pooled 254 studies and found the same thing nearly every time: the same study time spread over separate days produced better recall than the same time in one block. Spacing has the dates for a paper schedule.

Together they are the fastest honest answer to "how do I memorize fast": test yourself tonight and again tomorrow. Everything else on this page is a way of making those two recalls easier or more durable. Chapter 1 of the free playbook is the first of them, answer first, on one page.

Technique 2: Ask why (elaborative interrogation, and how to improve memorization of facts)

A fact with a reason attached is easier to recall than a bare fact, because the reason gives you a second route to it. Elaborative interrogation is the habit of turning each fact into a why-question and answering it. "The boiling point rises with hydrogen bonding" becomes "Why does the boiling point rise with hydrogen bonding?" and the answer, "because the molecules attract each other more strongly, so more energy is needed to pull them apart into a gas", is what you remember the fact by.

Pressley and colleagues (1987) studied this with adults learning sets of facts: the learners who were asked why each fact would be true, and had to produce the reason, remembered more of the facts than learners who simply read them. Dunlosky's review rates the technique moderate, and names its limit: it works when you have background knowledge to connect the fact to. If you do not yet know what hydrogen bonding is, "why?" has nothing to grip. Learn the idea first, then interrogate the facts around it.

The practical form: in the margin beside every fact in your notes, a question starting with "Why". Recall the answer, not the fact, when you review.

Technique 3: Draw it (dual coding)

Dual coding is the idea that words and pictures are stored by two different systems, so a fact you have both read and drawn is encoded twice (Paivio 1986). Mayer's research on multimedia learning finds the same from the other side: people learn better from words with relevant pictures than from words alone (Mayer 2009). Neither is a rating from Dunlosky's review, so call dual coding supported, not proven.

How to do it: a quick sketch beside every definition, even a bad one. A labelled diagram redrawn from memory, then compared with the source and every wrong or missing label circled. Redraw the diagram from memory is the science version. The honest limit is that drawing what you do not understand is decoration. A sketch of the Krebs cycle that you copied from the textbook is a copy; the one you drew from a blank page is a recall.

Technique 4: Mnemonic devices for lists you must hold exactly (how to memorize something fast)

A mnemonic is scaffolding for an M item. Four kinds, one school example each.

Acronyms. A word whose letters stand for the items in order. For the order of operations in arithmetic, a six-letter word covers brackets, exponents, division and multiplication, addition and subtraction. Build your own; a word you made is easier to recall than one you were given.

Rhymes and rhythm. A line with a beat holds an ordered list. The days in each month, the number of days in a leap year, a spelling rule. Short, exact, nothing else.

The keyword method. For a vocabulary pair, link the new word to a familiar word that sounds like it, through a picture. Useful for a language class; Dunlosky's review rates it low overall, because it helps with one narrow job and not with anything else.

The memory palace (method of loci). Walk a route you know well, your home from the front door to your bedroom, and place one item of the list at each stop as a vivid image. To recall the list, walk the route again. Maguire and colleagues (2003) studied ten people with superior memories, most of them competitors in memory championships, against ten matched controls. Nine of the ten memorizers reported using the method of loci for some or all of the tasks, and brain imaging found no structural differences between the two groups; what differed was that the memorizers engaged regions involved in spatial memory and navigation while they memorized (Maguire et al. 2003). Ordinary brains, a strategy. For a list of ten or more items in a fixed order, it is the strongest tool on this page.

The rule for all four: a mnemonic is scaffolding, and it must be followed by recall practice of the real list. The acronym is not the knowledge; the list it points to is. Say the acronym, then write the full list, covered, tonight and tomorrow. And a mnemonic does nothing for understanding. It will not tell you why the stages of respiration happen in that order, only that they do.

Worked example: one list to memorize, one rule to understand

The list. Grade 12 biology (SBI4U) asks you to know the stages of cellular respiration in order, and where in the cell each happens: glycolysis in the cytoplasm; pyruvate oxidation and the Krebs cycle in the mitochondrial matrix; the electron transport chain on the inner mitochondrial membrane. That is an M item: four stages, three places, a fixed order, no reason that a Grade 12 student could derive the order from.

A two-line story mnemonic in our own words, built on the first letters of the stages, G, P, K, E: "Glucose Pays the Kitchen's Electric bill." Glucose is split outside the kitchen, in the cytoplasm; the paying and the cooking (pyruvate oxidation, Krebs) happen inside the kitchen, the matrix; the electric bill is paid at the wall, the inner membrane. Silly on purpose; a silly image is a sticky one.

Now the scaffolding does its one job. Tonight: say the line, then write the four stages and three locations from memory on a blank page, check, and write them again. Tomorrow morning: write them again without saying the line first. If they come, the mnemonic has done its work and will fall away. If they do not, say the line once and try again.

The rule. Grade 12 advanced functions (MHF4U) uses the law log(ab) = log a + log b. Do not memorize it. Derive it once. Suppose a = bˣ and c = bʸ, for some base b. Then ac = bˣ · bʸ = bˣ⁺ʸ, because multiplying powers of the same base adds the exponents. Taking the log in base b of both sides, log(ac) = x + y. But x = log a and y = log c. So log(ac) = log a + log c. The law is the exponent rule, written for logs.

Check it with numbers, base 10: log(100 · 1000) = log(100 000) = 5, and log 100 + log 1000 = 2 + 3 = 5. The check is 5 = 2 + 3, and it is the kind of line you can produce in an exam when the formula will not come: pick two powers of ten and watch the exponents add. A derived rule carries its own check; a memorized one does not.

The techniques that feel like memorizing and are not

Each of these feels productive because it produces fluency: the page gets familiar, and familiar feels like known. None produces recall. Swap each for the thing beside it.

• Rereading. Read once, then close the page and write what you remember. The gaps are the study list.
• Highlighting. Instead of marking the line, write a why-question in the margin beside it.
• Copying notes out neatly. Copying is not recall. Rewrite them from memory instead, then compare.
• Listening to a recording on repeat. Hearing is reading at someone else's pace. Listen once, then recall the points covered.
• "Visualizing success." Picture the exam room all you like; it stores nothing. Picture the diagram instead, then draw it.
• Staring at a list until it "goes in". It does not go in. Cover it and write it; that is the only way to find out whether it did.

"How do I memorize fast?" The honest short version

Tonight: write the list from memory, check, write it again. If the list is ordered and must be exact, build a mnemonic first, then do the same. Sleep; the night stores the work. Tomorrow morning, write it again before breakfast. That is as fast as memorizing gets without losing it by Friday, and the second morning's recall is the step most people skip. If the test is tomorrow and the list is long, what one night can buy is the honest plan for the evening. For the few formulas you must hold exactly and cannot derive, write a card for each and let recall do the rest.

The ranking in six lines

1. Recall it, notes closed, before you look. The strongest technique there is.
2. Space it: again tomorrow, again in a few days, again in a week.
3. Ask why for every fact that has a reason, and recall the reason.
4. Draw it beside the words; redraw it from memory.
5. Mnemonics for ordered, exact lists only, followed by recall of the real list.
6. Rereading, highlighting and copying rank last; swap each for a recall.