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What is comparative assessment and how can teachers use it in their classroom?

By Alan Peters,

24 Jan 2020

Every school has them; the tickers, the flickers, the essay writers and the deadline fighters.

Marking; the bane of teacher’s lives.

Would it be that there was a form of assessment that was less time consuming, but also accurate and – importantly – useful. Perhaps there is some good news, because one of the oldest forms of marking, comparative assessment, is making a comeback.

Is it worthy of the hype? There are those that swear by it; those that are bewildered by the prospect of forking out an annual fee of £500 plus for a scheme that, fundamentally, gets us to do the work; those that see it as rather missing the point of marking.

After all, is it assessment for the child, or to produce a set of statistics? It needs to tell us more than that children progress more quickly with Miss Markallnight in Year 5 than they do with Mr S (for Speedy) Gonzales in Year 4.

Something which any curriculum leader half worth their salt would already know. A Brief Resume of Comparative Assessment In 1927 a psychologist, Louis Thurstone, published a paper on the nature of comparative judgements.

Often, he concluded, this type of assessment is the most accurate. And that is the basis of comparative assessment.

Teachers compare several pieces of work on the same topic, for example a set of stories, or a science write up.

They rank them, and then analyse in detail the extremes of their results.

They use this information to make judgements about learning and teaching. The system works best when multiple teachers make the assessments; the process also can be beneficial worked through with students.

Mr Gonzales will be delighted.

His traditional marking features a flick through the pages of his students’ work, a large tick, a letter in a circle (nearly always a C) and a comment, which reinforces the letter.

‘Good’ works well for him, since it is nicely ambiguous, and consists of only four letters. With comparative assessment, he can get his pupils to do the marking as well.

Brilliant. But for more professional colleagues, anonymised work studied by students who have tackled the same task themselves can provide some handy peer learning.

A+ For the Following Research indicates that comparative assessment is more accurate than traditional assessments made against set criteria.

That probably makes sense.

Each piece is contrasted to numerous others; three teachers working together might be looking at close to a hundred scripts, scanning each quickly while the ideas they have seen illustrated in other children’s attempts is still fresh in their minds. The dialogue between teachers as they complete the assessment is also a useful tool for fine tuning judgements. The system definitely works best for open ended tasks, especially creative ones.

Where an assignment has a strong factual element, it is less successful, since the teacher will still need to assess each element being tested.

So, for example, a maths paper still needs to be marked in a more traditional way. But when comparative assessment can be used, for example in marking a series of essays, it undoubtedly speeds up the marking process and allows teachers to achieve a better balance in their work.

Although Mrs Colon, who religiously checks every spelling, every punctuation mark, ensures that every letter is perfectly formed and then sets about writing a comment longer than the piece she has just marked, might wonder what to do with the time on her hands.

Commercial providers suggest that a group of teachers (number undefined) can mark a set of stories (length, number, age of student also undefined) in an hour.

Impressive, although in total staff hours perhaps not a lot quicker than traditional marking.

However, working through a class set is a lonely and, frankly, boring task.

Sharing it with colleagues, and discussing choices and rankings, might make the process more palatable. Finally, comparative assessment challenges the way we operate.

As Mr Gonzales says, all the kids want is their work back with a grade in a box.

Perhaps he is right, but having to compare exemplars to their own work, and make judgements accordingly is almost certainly a more worthwhile process than even reading Mrs Colon’s comments. And as for that Assistant Head (curriculum) who has written the world’s longest, most meaningless and impossible to operate (except for her, because she wrote it) marking scheme – her job is completely out of the window.

Hurrah. Comparative assessment means work will be returned having been seen and judged by teachers but reviewed by the student themselves.

Parents will no longer be able to rank a school by the length of a teacher’s comment, and students will set their own, challenging, targets.

Could Do Better But comparative assessment is not some panacea which will free up teachers’ time and cast a sunny glow over our lives.

As we saw above, it is not a good fit with every subject area. It is also limited when it comes to getting to know a particular students’ strengths and weaknesses.

Certainly, we will get an accurate idea of their overall progress and achievement compared to others, but we will find it harder to break this down into specific targets. Advocates would argue that the students, with some metaphysical inspiration, will do this for themselves.

Fine when it goes well; but much less effective when our pupils are learning a new way to assess their work, and especially when he or she is struggling. Monetarising Student’s Progress: Commercial Opportunities As might be expected, some commercial enterprises are looking to cash in on the old new trend.

One such company is the evocatively named ‘No More Marking’.

This organisation seeks to bring teachers together, at a cost, and allow them to share assessment tasks.

It offers some exemplars of writing, which are fairly comprehensive, and grades each in a number of ways. Again, while that is useful, it does not overcome the fundamental issue with comparative assessment of not breaking down a pupil’s success or otherwise into clear, identifiable concepts. In addition, it seems a little cheeky to be cashing in on the fact that teachers are working together to provide the company with data, albeit information it then shares with its members. Although empirically based, the judgements were still somewhat subjective.

A piece of Year 6 writing which it placed in the top 0.001 %, while undoubtedly good, still suffered from adjectival diarrhoea, and too many ‘magic’ words where a simpler alternative would have provided a better fit. Comparatively Speaking, Is It Worth It? Comparative assessment is certainly worth considering, especially for teachers of arts-based subjects where success criteria is subjective.

It is probably not worth investing some hard-won budget in the process, but better to work together within and between schools to establish a data base of standards of work.

There is plenty of material out there, free to use, to supplement this. At the end of the day, it won’t make Mr Gonzales a better teacher, because he won’t commit to it.

But for the rest of us, comparative assessment is worth a look. Anything that promises to reduce teachers’ workload by an hour or two a week should certainly be up for consideration.


1- Increasingly complex technology calls for better assessments

2- Accurate assessment in early years foundation stage

3- Is the new draft Welsh curriculum showing the way forward?

4- Top tips to help you minimise your marking