How to Choose Your Leaving Cert Subjects

You pick your Leaving Cert subjects once, and then you live with that choice for two years. It sets what you study every week, what you sit in June, and which college courses stay open to you. This guide walks through how to make that call with evidence rather than guesswork.

When you actually choose

Most schools ask you to choose near the end of Transition Year, or at the end of 3rd year if you go straight into 5th year. You usually pick a set number of subjects from option blocks the school builds, so your real choice is often "which subject in this column", not "any subject in the country".

Two practical points follow from that. Blocks change per school, so the combination you want may not be offered, and popular subjects can fill. Ask the guidance counsellor for this year's option blocks early, before you settle on a plan that the timetable rules out.

What you don't get to choose

Before you weigh options, separate the fixed part from the free part. Most students carry English, Irish and Maths the whole way through, so those seats are usually spoken for already. Irish has exemptions in specific cases (you can check the criteria on gov.ie), but for most students it stays on the timetable.

That means the decision you are really making is about the remaining option subjects. Spend your energy there.

Start with the exam, not the description

Subject descriptions on curriculumonline.ie tell you what a subject covers. They do not tell you what the exam feels like, and the exam is what you sit in June.

So before you commit two years to a subject, open a recent past paper and read it as if you had to answer it. A Business paper asks you to write structured answers and apply theory to a scenario. A Physics paper asks for calculations, definitions and experiments. A History paper asks for long, evidence-based essays. These are different kinds of work, and reading one real paper tells you more about the fit than any brochure.

You can do this for free. Our past paper finder holds Higher and Ordinary Level papers from 2015 to 2025 across the main Leaving Cert subjects, with the official marking schemes beside them. Try the Business past papers and the Biology past papers side by side and you will feel the difference in five minutes. Read the paper, then read the marking scheme to see how marks are actually awarded. If the way a subject is examined puts you off, that is useful information now, not in April of 6th year.

Check the course requirements yourself

If you already have a college course or career in mind, some subjects can be a hard gate rather than a preference. A course can list a minimum entry requirement: a specific grade in a specific subject that is non-negotiable. A high points total will not substitute for it.

Rather than trust a list that can change year to year, learn to check the current requirement yourself. Three official sources cover almost everything:

• cao.ie is the Central Applications Office, the single site you apply to Irish colleges through. Each course listing states its entry requirements.
• qualifax.ie is the national course database. You can search a course and see its subject and grade requirements in one place.
• The college's own website is the final word. When two sources disagree, the college page for that exact course wins.

A few patterns are worth knowing so you know what to look for. Many courses at the National University of Ireland colleges (UCD, University of Galway, UCC and Maynooth) ask for a pass in a third language, meaning a language other than English or Irish, though several courses now have exceptions. Entry to primary teaching has a specific Irish grade requirement. Some engineering and science courses expect Higher Level Maths or a laboratory science. Do not take these as settled facts for your year: look up the exact course on the three sources above and write down what it actually says.

If you are genuinely unsure what you want to study, keep one language and at least one laboratory science on your list. That combination keeps the widest range of courses reachable without forcing a career decision at fifteen. If it helps to talk a shortlist through, you can also put the question to our AI tutor, which knows the papers and can walk you through what each subject actually asks of you.

Higher or Ordinary is a later decision

Choosing a subject is not the same as choosing its level. You sit the exam at Higher Level or Ordinary Level, and in most schools you can move between the two well into 5th year, sometimes into 6th year, depending on the subject and the timetable.

So do not rule a subject out because you are worried about coping at Higher Level on day one. Take the subject, start at the level your teacher advises, and let the first term of real work tell you where you sit. The past papers help here too: the Higher and Ordinary papers for the same subject and year are both in the finder, so you can compare exactly what each level asks before you decide.

Play to your strengths, keep doors open

Two ideas that pull against each other:

You will study these subjects for hundreds of hours, so a subject you have some genuine interest in or ability for is easier to sustain than one you picked only to tick a box. Interest does real work over two years.

At the same time, a spread that leaves several course areas open is safer than one that bets everything on a plan you might change. Most students who think they know their exact course at fifteen change their mind at least once.

The workable middle is this: choose subjects you can stand to study, make sure any hard requirement for a course you are seriously considering is covered, and beyond that keep the spread wide. You do not need to optimise a career from a school corridor. You need to avoid closing a door you will want later, and avoid a subject you already know you will dread.

FAQ

When do I choose my Leaving Cert subjects? Usually at the end of Transition Year, or at the end of 3rd year if you skip TY. Ask your guidance counsellor for this year's option blocks, because the school's timetable decides which combinations are actually available.

How many subjects do I take? Most students sit six or seven for the Leaving Cert, with the best six counting for CAO points. Your school sets the exact number and the option blocks you choose from.

Can I change a subject after I start 5th year? Often yes, early in 5th year, if the timetable allows and there is space in the class. It gets harder the longer you leave it, because you have more to catch up. Talk to your year head as soon as you have a doubt.

Do I have to decide Higher or Ordinary Level now? No. You choose the subject now and can usually settle the level later, often into 5th or even 6th year. Read the Higher and Ordinary past papers for the subject to see what each level asks.

How do I know what a subject's exam is really like? Read a recent past paper and its marking scheme. Both are free in our past paper finder, so you can see the real questions and how marks are awarded before you commit.

Not sure how a subject is examined? Open the past paper finder, read a recent paper with its marking scheme, and see exactly what two years of that subject builds towards before you choose.