HESI A2 study guide: the ten topics, and the order to take them

Ten topics, each with the question it answers and the guide that answers it, plus three passes — sort yourself, teach one topic at a time, then check and expect to be wrong.

A HESI A2 study guide is not a book you read once. It is a route through ten topics — three of them science, four of them math, three of them language — and the route that works is the one ordered by the sections your nursing program actually requires, not by what a prep book puts first.

That is the whole design of this page. Below are the ten topics this course teaches, each with the question it answers and the guide that answers it, then three passes through them: a sorting pass that tells you where you are, a teaching pass that fixes the ideas, and a checking pass that finds what did not stick.

Read this before you plan anything

Two constraints decide your plan, and neither is about study technique.

Your program chooses the sections. A testing center publishes the form it delivers, and one college's page says it plainly: "Individual programs will determine the sections required for application." Ask your program which sections it wants — in writing, if you can — because two of the ten topics here (biology and chemistry) may not be on your form at all, and even in anatomy the deeper chapters may not be asked — a month spent on a section nobody requires is a month not spent on one that decides your admission.

The owner publishes no per-topic breakdown. When this course was built, Elsevier's own pages were read for one and none exists, so no page — this one included — can tell you that one topic is worth more than another. What can be said is what each topic asks of you, and that is what the table below gives: not a ranking, a description. If a site hands you percentages for these ten topics, ask where the number came from, because the owner publishes none.

The ten topics

Topic	The question it answers	The guide	Start here if
Basic operations	can I work whole numbers, fractions, decimals and percents without a calculator error?	basic operations	arithmetic feels slow or you reach for a calculator for 3/4 + 5/6
Ratio and proportion	can I set up a relationship and solve it for the missing term?	ratio and proportion	word problems about rates, strengths or scales go wrong at the setup
Measurement and conversion	can I move between units — metric, household, time — and keep the value?	measurement and conversion	you know the arithmetic but lose marks converting
Dosage calculation	can I get from a concentration and an order to a volume, and from a rate to a flow?	dosage calculation	the math is fine but the clinical wording is not
Reading comprehension	can I say what a passage claims, and what it only implies?	reading comprehension	you read fast and miss the scope of a claim
Vocabulary	can I get a word's meaning from the sentence, or from its parts?	vocabulary	medical words look like long strings of letters
Grammar	can I write a sentence that holds together, with punctuation in the right places?	grammar	you punctuate by ear
Biology	do I know the cell, inheritance and the phases of division?	biology	your program requires the biology section
Chemistry	do I know atoms, bonding, reactions, solutions and acids?	chemistry	your program requires the chemistry section
Anatomy and physiology	can I name a system's parts and say what the system does?	anatomy and physiology	your program requires the section — it needs the longest lead time of the ten, so start it early even though it is last in this table, and allow two study sessions for it

The four math topics are one strand and they build in that order: operations before proportion, proportion before dosage, and measurement running alongside both. That is the order the table is in, and basic operations first is the default order to take the ten in — unless your program's required sections say otherwise. There is one exception, and it is about timing rather than order: anatomy and physiology needs the longest lead time of the ten, so start it early even though it sits last in the table. The A&P guide is deliberately the longest thing on this site, because that section carries the most new vocabulary of the ten — and vocabulary is learned by technique, not by talent, which is why that guide teaches each system by its job instead of as a list of organs.

Pass one: sort yourself

Before teaching anything, find out which topics are already sound and which are not. Each guide opens by stating what the topic actually asks of you and then gives a short set of procedures or checks; read those openings in one sitting, ten topics in an afternoon, and mark each one mine, shaky or not on my form.

Two things make this pass worth the afternoon. It stops you studying the topics you enjoy, which is the usual failure; and it surfaces the topic you have been avoiding, which is the one to give extra study sessions to. If nothing else, do the math strand's sort properly, starting with basic operations — the first topic in the table and the first in the strand: the four math topics are the ones where a wrong answer is unambiguously wrong, so they tell you the truth about your preparation faster than any vocabulary list.

Pass two: teach, one topic at a time

Take one topic per session, no more. A session that works has three parts:

Read the guide's procedures section, not the prose first. Every guide in this course states the steps, then explains them. Read the steps, close the page, and write them from memory. What you cannot write, you do not know.
Work the guide's own examples with the answer covered. Every worked example is there to be re-worked, not read. The failure mode is nodding at a solution someone else did: practice producing the answer before you look at the choices.
Say the idea out loud in one sentence. Systems in A&P, phases in biology, word parts in vocabulary: if the sentence will not come out, the idea is still a list of words.

The glossary exists for the words that stop you mid-sentence: each term has its own short page, written to be read in under a minute, and each one points back to the guide that teaches it in context.

Pass three: check, and expect to be wrong

A checking pass is where most study time is lost, because it is usually spent re-reading. Re-reading feels productive and measures nothing. Three checks measure something:

Redo the guide's examples a week later, from the question only. A method you can restart cold is a method you own.
Write the traps down. Each guide lists the mistakes that topic invites — a conversion that runs the wrong way, a percentage taken of the wrong base, a word part misread as a different root. Those lists are short, and they are the highest-value thing on this site after the procedures themselves.
Practice in the order your program's sections will come, as far as you can learn it. If your form starts with reading, do not spend your last week only on A&P: a sitting moves between subjects, and your final week is the cheap place to practice the switch.

What this course does and does not give you

The ten guides are written against the content of each section and are sourced: where a fact belongs to a body of published knowledge — a normal value, a unit definition, a rule of grammar — the guide cites it, and where a guide teaches a technique, it shows the working rather than asserting a result.

All ten practice sets are open, and a free set is real questions rather than a sample of three. The guide's own examples stay the worked model for each section; the practice set is where you answer without one. How many questions the exam has is a separate page, because the answer is one college's published form rather than a national number, and it is worth reading before you plan your last two weeks. Which sections your program counts and what its cutoff is are separate pages for the same reason: both are the program's decision, not Elsevier's.

HESI A2 is a trademark of Elsevier Inc. Elk Ridge Academy is not affiliated with or endorsed by Elsevier.