How to use grade boundaries in A Level chemistry (and the mistakes you should avoid)

I’ve had a lot of students ask me questions about grade boundaries recently, so I thought I’d write a post explaining a bit more about where grade boundaries come from. Although they are a useful tool in some situations, I don’t think it’s a good idea for students to obsess about them, so I’ve given some more useful ideas at the end for students to check progress in the summer exam season.

Why do grade boundaries change each year?

After the exams are sat by students and marked, senior examiners determine the boundaries for each grade. This is a complex process but mainly takes into account the following data:

• How easy or difficult students found the examination
• How the results of students compared to previous years
• How the results compared to the expected ‘profile’ of this group of students (based on standardised national tests and GCSE results)

Are exams getting easier or harder?

This is a question as old as exams, and the answer is generally no to both. The style of questions can change, the feel of an exam can be different but there really isn’t evidence to suggest exams are easier – or harder – than they used to be.

If papers stay roughly the same level of difficulty each year, it is likely that the grade boundaries may increase slightly. This is because, with more past papers available, most students will have been able to practice more of a similar sort of question, so they will get better marks than previous years. This is also why exam boards try to ‘mix it up’ – and why you sometimes come out of an exam thinking ‘that’s nothing like previous years!’.

How can grade boundaries be useful?

As a scientist, I’m a big fan of using data and that it is better to be well-informed. There are definitely ways that grade boundaries, in combination with past paper practice and mock exams, can be useful:

• Tracking progress through your A Levels: grade boundaries are a useful tool to inform teachers and students about whether they are making expected progress.
• UCAS applications: it’s useful to know what you’re likely to get in your A Levels before applying for higher education.
• Difficulty of the paper: if you find a paper very challenging, it’s useful to know if this is because it’s a particularly difficult paper, or due to an issue with revision or exam technique.

Problems with using grade boundaries

Although grade boundaries can be useful, there are lots of ways I see students (and teachers) using them poorly. 

• Problems with the data used: due to disruptions from the pandemic, it’s quite difficult to draw useful conclusions from the data from the last five years. For 2020 and 2021, most grades were awarded by teachers and not by students sitting external exams. Smaller cohorts of students can skew the data a lot. From 2022 and 2023, grade boundaries were slightly modified to recognise the disruption to learning from previous years.
• Looking at a single A Level or AS Level paper: grade boundaries are issued for individual papers by exam boards, but these are a rough guideline only. You should always compare your results for all three papers, especially since Paper 1 and Paper 2 generally test very different content.
• Wasting valuable time: if you’re taking your A Level exams this summer, I would argue that your time is mostly wasted checking grade boundaries. Knowing what grade you might have got in that paper isn’t going to improve your grade in the real thing, so below I’ve given a few suggestions on what you could be more usefully doing.

Alternatives to using grade boundaries

Feedback is important, but grade boundaries aren’t always the best way to do it. To use time more effectively, these are the steps I recommend to students after completing a paper under exam conditions:

• Look for ‘risky’ marks: when using the mark scheme, look for marks that you got through the ‘allow’ column. How many are there? How could you improve your answer so you are more likely to get this mark next time?
• Look for 10 marks you should have got: these could be marks you lost due to lack of knowledge – put them on a flashcard or make a note to revise that topic more. Alternatively they could be marks due to careless errors – make a note of why you got it wrong, and remind yourself of this just before you do the next practice paper (or the real exam!)
• Use examiner’s reports: these are available for each year and give a useful summary of the common mistakes students make, along with the questions students found the most challenging. 

A note on predicted papers and grade boundaries: I don’t include grade boundaries on my predicted papers, due to the limitations mentioned above. If you check the table below, you can see the range of percentages for each grade for the three main exam boards over the last few years. 

Want some more exam practice with detailed feedback and explanation? All my predicted papers for A Level chemistry come with full mark schemes and video walkthroughs.

Looking for some expert ‘last minute’ support to get you to your target grade for A Level chemistry? I have some spaces available in my three pre-exam revision classes for Papers 1, 2 and 3, starting 7th June.