How to Memorise Science Subjects Without Cramming

Biology, Chemistry and Physics are full of things to remember. Here is how to make them stay.

Open a Biology textbook and the facts come at you in waves: stages of cell division, parts of the heart, the names of enzymes. Chemistry gives you the periodic table, reaction types and a long list of exceptions. Physics piles on formulae and units. It can feel like the only strategy is to stare at the page and hope.

Staring does not work, as most of us have found out. But the good news is that science is easier to memorise than it looks, because most of it is connected. Once you see how the pieces fit, and use the right practice, a lot of it sticks. This guide covers what to do.

Understand first, then memorise

Trying to memorise something you do not understand is the slowest way to learn it. Take the heart. You can memorise “blood goes from the right atrium to the right ventricle to the lungs” as a string of words, and it will fade in days. Or you can understand why: the right side takes blood to the lungs to pick up oxygen, the left side sends it to the body. Now the order is not a list, it is a story, and you can rebuild it even if you forget a word.

So for each topic, ask “why is it like this?” before you try to remember it. Then memorise what is left, the names, symbols and numbers. They will have something to attach to.

Draw it from memory

Science is full of diagrams: cells, circuits, the water cycle, apparatus for an experiment, reaction pathways. Do not just look at them. Study one for a minute, cover it, and draw it from memory with every label you can recall. Then compare with the original and fix what you missed.

This is active recall, and it works especially well for science because the picture and the words reinforce each other. One diagram drawn from memory three times across a week will stay far better than a diagram looked at ten times.

Make mnemonics for lists

Some things really are lists with no logic: the order of the planets, the first ten elements, the cranial nerves. For these, a mnemonic helps. Take the first letter of each item and make a silly sentence, or make a rhyme or a short story.

• Make your own. The effort of inventing it is part of what makes it stick. A strange or funny one is easier to remember than a dull one.
• Keep it short. A mnemonic should take less effort to remember than the list itself.
• Use rhythm and sound. Many Ghanaian students remember best by chanting. If a rhythm works for you, use it.
• Use a familiar place. Some people place each item along a walk through their house or school, picturing it at each spot. It is an old technique, and it can work well for a long ordered list.

Learn formulae by using them

A formula you have only read is fragile. A formula you have used on ten problems is solid. So after learning one, go straight to questions that need it. Write the formula at the top, name each symbol and its unit, and work the problem. Then, later in the week, try to write the formula from scratch before you check it.

Also learn how formulae connect. In Physics, many are rearrangements or combinations of a few base ideas. If you understand where v = u + at comes from, you do not have to memorise as much separately.

Chunk, then test

Large topics are hard to hold in one piece. Break them into chunks of five to seven items or steps, each with a short label. For the stages of respiration, for instance, learn the three stages as one chunk and what happens in each as sub-chunks. Then test yourself: first the chunk labels, then the contents.

Space it out

Science needs repetition, but not all in one sitting. Review a topic the next day, then a few days later, then a week later. Each time, test yourself instead of reading. Short sessions of 15 to 20 minutes on three or four topics are better than one long session on one. Our guide on spaced repetition has a schedule.

Use past questions to see what matters

You cannot memorise everything equally, so let past questions guide your emphasis. Notice which facts, definitions and diagrams come up again and again, and make sure those are solid. Then check that you can answer in the form the exam wants: a definition in a sentence, a labelled diagram, a calculation with units.

A sample week for one topic

• Day 1. Understand it: read, make notes, ask why. Draw the key diagram and try to label it from memory.
• Day 2. Test yourself: write what you remember, draw the diagram, answer five questions.
• Day 4. Redo the diagram and the questions you missed. Add a mnemonic for any list.
• Day 8. Short test: a past question on the topic, timed.
• Day 15. A final quick recall, then leave it until before the exam.

Mistakes to avoid

• Copying notes out again. It feels like memorising, but it is a lot of effort for little recall.
• Memorising without understanding. It will not survive a question worded differently.
• Only reading the diagram. Drawing it is the practice.
• Skipping units. A correct number with the wrong unit can lose marks.
• Leaving it all until exam week. Science memory needs spacing.