Junior maths challenge 2025

Bravo, you are sharp. 😂

I'm not going to start anything new at 2pm on a Friday as well. I'm just trying to clear up random stuff before the weekend.

The picture shows four yellow ties, a purple tie and one obscured. The school's website indicates that purple ties are Year 7 and yellow ties are Year 8. Year 9 wear blue ties.

I have way too much time on my hands today.

I saw some social media posts....but....just thinking most seem to be NI. Their yr9 is our yr8.

Here's one English example though.

https://x.com/ErnestBevinAcad/status/1928451802183180766

@Jonny234 Maybe say 10%-15% of the candidates are non year 7/8?

I don't know the exact number, but I know some high mark kids who took it in Year 7, weren't doing it for the first time. They may have been taking part and practicing it since Year 4 or 5.

@Jonny234

I've also seen social media posts with yr9's taking it too. Maybe say 10%-15% of the candidates are non year 7/8?

The JMC? It's supposed to be for Year 8 and below. Some primaries do give it Year 6s and even Year 5s but I wasn't aware that Year 9s are allowed to take it. They're supposed to take the IMC.

Under the old marking scheme, students who attempted the last 10 questions, whether they got them right or wrong, could be just guessing randomly, not aware of exam techniques.

Under the old scheme, students who guessed randomly on the last 10 questions would have got two right on an expected basis for +12 points but would have got eight wrong for -12 points, netting out to 0. That was the purpose of the negative marks. Under the new scheme, they'll still get +12 for the two correct answers but will not lose any points for the wrong ones for a net score of +12.

It's not relevant whether students are aware of optimal strategy or not. If they guess on the last 10 questions or, for that matter, make mistakes that aren't guesses, they'll get higher scores under the new scheme than under the old one.

But to what extent this affects the grade boundaries is still unclear and depends on a lot of assumptions.

Absolutely. I've provided a lot of information and I believe that I've been clear about my assumptions. You're free to make whatever assumptions you please and draw whatever conclusions you wish.

if they use optimal strategy and just fill in guesses for the remaining questions

Not all students — especially those who didn’t reach the last 10 questions — would have used that kind of strategy. Under the old marking scheme, students who attempted the last 10 questions, whether they got them right or wrong, could be just guessing randomly, not aware of exam techniques. So the change in marking scheme, by itself, likely raised the overall average score. But to what extent this affects the grade boundaries is still unclear and depends on a lot of assumptions.

@Jonny234

Are there more marks these days?

Yes. Before Covid, points were deducted in the JMC for incorrect answers on Questions 16-25. After Covid, no deductions were made for incorrect answers. The effect is to add 12 points, on an expected basis, to the scores of children who cannot access the last 10 questions within the allotted hour if they use optimal strategy and just fill in guesses for the remaining questions. This effect diminishes for children who are able to access some of the last 10 questions, to zero for a child who can do all 25 correctly.

Before Covid, a "typical" JMO qualifying score corresponded to about 20 correct answers. At that level, this change should have added one more correct, albeit randomly guessed, answer, or about 6 points, to the qualifying score. The actual increase in the JMO qualifying score has been more like 15 points.

That said, I found Questions 23-25 on the JMC to be noticeably easier on the post-Covid papers than on the ones before.

I think this is related and intentially, related to the change of marking scheme compared to the pre-COVID years.

Foxhasbigsocks I can see your point. I believe generally any kangaroo will be at a level higher than the class level at school and will relish the extra challenge. Even the question level of the 1st JMC paper will be higher than what they are used to normally. Kids capable of this will relish the challenge.

The Olympiad is totally different. I think my DD would relish it if it was more of the same multiple choice but the mature style questions and marking system of the Olympiad dont just make it advanced on the difficulty of questions but also on the full workings requirement. The latter she is not developed in by any means so for her it's more a case of preparation for more advanced maths in the future rather than being about the grade outcome of the test.

On a good day with the right questions she may be able to answer 3 or 4 questions but in doing so may only pick up 15-20 marks. The challenge is adding another 10-15 marks to this with more detailed workings.

PreplexJ That makes sense. I've also seen social media posts with yr9's taking it too. Maybe say 10%-15% of the candidates are non year 7/8?

For the remaining candidates, then perhaps 2/3's of the qualifiers are boys, and 2/3's yr8?

There was a post on here stating at older ages boys do a lot better than girls in the olympiads, so perhaps 2/3s by only works at kangaroo level and rises for olympiad.

@Jonny234

Are the kids better prepped? Questions easier?

Probably some of each. I infer from the remark on the JMO markers report indicating that more JMO participants are following instructions and attempting full solutions that more JMO qualifiers are being prepared for the JMO, at least to the extent of being taught the format and the rubric, whether by their math teachers, parents, or tutors. I would further guess the preparation extends to the qualifying exam as well.

That said, I found Questions 23-25 on the JMC to be noticeably easier on the post-Covid papers than on the ones before.

While I agree that the best part of Olympiad math is the opportunity to think deeply, this doesn’t necessarily apply to the JMC or Kangaroo levels. With some preparation, exam techniques, and targeted tutoring, scores can easily be boosted by 20–30 marks. And the JMO related turoring class is a blooming business in recent year among some group of parents. This creates a distortion in the result distribution between those who receive specific preparation and those who don’t. I'm commenting on the general trend in general, particularly the recent surge in high scores, it is a phenomenon rather than referring to any specific case or family.

Quite sweeping comments :). My year 6 child has not done any JMC paper. My elder child only started from year 8(and we are Asian). Beast Academy is really fun at this age if the child is keen. The best part of Olympiad problems is it requires deep thinking.

Are there more marks these days? Are the kids better prepped? Questions easier?

I believe the recent increase in the number of top students can partially be attributed to the growing popularity of specialized Jmc tutoring classes—both online and in-person—designed specifically for exam questions preparation. This trend is particularly strong in Asian/East Asian communities, where families often emphasize early and intensive preparation for math olympiad, kids are put forward to take JMC from year 4/5. I’d be very interested to see the demographic breakdown of participants in the JMO/Kangaroo, but unfortunately, I don’t think the UKMT collects that information.

There are definitely some really interesting questions around the point of all of this. My ds is through to Kangeroo but from a parental point of view I’m less interested in his grades or trying to distinguish between the top mathematicians in the country than him having the opportunity to really enjoy doing some challenging maths and grow as a mathematician. He thoroughly enjoys the challenge type questions and finds them stretching.

I think the higher grade boundaries for follow on rounds are unfortunately going to mean that in many schools where there is little or no prep for these challenges children will have less chance of moving on to the follow on rounds.

I also wonder whether an experience of eg the Olympiad as being so hard even for the children in that category will ultimately be off putting for many of them? The MOG format sounds good from a learning perspective.

As a comparison point, it’s interesting to reflect that at the specialist music schools the children do not tend to do music grades and instead focus on mastery/challenging repertoire and growing as musicians. I do wonder whether focus on the marks here is where these competitions should be going.

Would it be better to have challenge style live events where mathematically able children could spend an enriching day learning about these sorts of problems?

user149799568 as always, sensible valid points.

Out of interest what is your take on the increase in the values for top qualification thresholds? The last 2 yrs olympiad 123/ 125 is very high and this yrs 100 Kangaroo is too. 123 and 125 doesn't sound like a lot but at that level there must be a fair few 123's and 124's.

ukmt.org.uk/junior-challenges/junior-maths-challenge-awards

Are there more marks these days? Are the kids better prepped? Questions easier?

If there isn't a definitive answer you're aware of gut feeling is fine.

@Jonny234

Perhaps increase the difficulty gradually over the course of the paper?

This is already the case in all math Olympiads which I'm aware of, including the JMO (the second paragraph in the markers report I linked to earlier refers to this). For that matter, I believe this is the case in all the UKMT first round challenges as well.

Do they really want to set the exam where the mean mark is somewhere between 1/4 and 1/3?

The very first paragraph in the 2024 Markers Report reads "This year’s paper [2024] turned out to be one of the easier papers in recent years, roughly similar to last year’s paper [2023], with correspondingly high thresholds for awards. The setting committee will be taking note of this when setting next year’s paper." I don't know how you read that, but that sounds kind of ominous to me. I read it as though they preferred the 2022 outcome to the 2023 outcome. As you pointed out, the mean score on Section B in 2022 was 25%. And the median score would have been lower than that because of the skew.

Actually, they don't care much about the mean or median scores. What's more important to them is that they be able to distinguish between the top 40-200 candidates, the medalists. That said, I suspect that they would be happy with a score distribution like the following, assuming 1460 children write the paper like last year:

Q1: 1300 make good progress (7-10 points on the question)
Q2: 949 make good progress (top 65% will get a Certificate of Merit)
Q3: 365 make good progress (top 25% will get a Certificate of Distinction)
Q4: 200 make good progress (they intend to award 100 Bronze Medals)
Q5: 100 make good progress (they intend to award 60 Silver Medals)
Q6: 40 make good progress (they intend to award 40 Gold Medals)

A score distribution like this would result in a mean score around 20, with a median score a couple of points lower.

Of course, it's never that clean, not every child who can do question 6 will necessarily be able to do all of questions 1-5.

"My guess is that UKMT will do something like they eventually did on the MOG: break the first couple of questions into parts that will lead more candidates towards a solution, or at least allow them to make some progress. However, since they're still allowing 2 hours for only 6 questions, I'd also guess that they will make the last couple of questions more difficult."

We don't know but I do think this is a very good shout, and probably makes my comments of yesterday obsolete. There seems little value in setting the exam at a difficulty level where the averages would I expect be in the low 20's (say 35%-40%) which it probably would be after dropping section A and following the same format.

2022 and 2023 Markers reports have actual mean's provided for sections A and B.

2022 (5.71+15.4)/70
2023 (6.8+22)/70

Assuming Section A average was 6 marks in 2024 with a mean of 27 would give a section B mean of 21. So the average of the section B's in the last 3 years is under 20 marks. Do they really want to set the exam where the mean mark is somewhere between 1/4 and 1/3?

So what are they likely to do? Like you say maybe split some questions into parts, with maybe 2-4 subquestions for some of them giving an opportunity to pick up marks. Perhaps increase the difficulty gradually over the course of the paper? I suppose there are a few options. What would surprise me is if the exam followed the existing section B format.

Both my children love the Olympiad type of question, sometimes for the same problem presenting different solutions to get to the same result. Practising Olympiad problem is also fun, sometimes it takes days and loads of revisit to be able to answer a question. It doesnt need as much repetitive practices as multiple choice type. So for the first round, my elder daughter often score high enough to get to the Olympiad but was not aiming for absolute mark. The fun begins at the Olympiad round for her.

Section A was always a bit of an anomaly in the JMO. None of the other math Olympiads (Cayley through BMO2 and, ultimately, IMO) have any answer-only questions, with the exception of the MOG in the last few years. UKMT have always shown that they care much more about generalizable solutions rather than specific answers which could be guess-and-checked or brute-forced, with the markers reports consistently stating that correct answers received very few points if not supported by fully justified reasoning. In the last few years, they've taken this to an extreme as they've placed literally zero weight on Section A in awarding medals.

My belief is that Section A served as a bridge between Challenge style questions (answer-only multiple-choice) and Olympiad style (full solutions required). The first time a child takes the JMO is usually the first time they see that type of question ("prove this statement" or "provide an answer and show why this answer alone is correct") requiring that type of solution. Section A existed to ensure that all candidates were able to make some progress and weren't left twiddling their thumbs for two hours. It seems that UKMT are no longer so concerned about that issue, with a recent markers report stating "Usually we would see many candidates attempt Section B in much the same way they attempt Section A, by this we mean that they find a correct answer but do not provide any written explanation to accompany it. For this paper this wasn’t generally the case and it appears that candidates are taking notice of the instructions on the front of the paper."

My guess is that UKMT will do something like they eventually did on the MOG: break the first couple of questions into parts that will lead more candidates towards a solution, or at least allow them to make some progress. However, since they're still allowing 2 hours for only 6 questions, I'd also guess that they will make the last couple of questions more difficult.

I think it's going to be interesting to see how the Olympiad distribution of marks pans out this year as a result of the changes. The 2024 markers report has a frequency distribution and other info.

Mean 27, Median 26

Merit 20+ (A and B combined)
Dist 38+ (A and B combined)
Bronze 38+ (B only)
Silver 43+ (B only)
Gold 50+ (B only)

Assuming the old section A is generally easier than B even though I agree it's an inefficient use of time at least it gave entrants the opportunity to get some "easier" marks. That's gone now.

I wonder if in 2025, Merit level could be as low as 15? Dist maybe low 30s, and the averages in the low 20s? Medal levels largely unchanged?

Someone above suggested that recently a decent amount of candidates were skipping section A entirely in order to spend more time on Section B.
Previously it was just 1 mark each for the 10 questions of section A so total max 10 marks for the section. Then section B was 5 questions each worth up to 10 marks each, so total 50 marks available in section B. Total for paper of 60 marks.
It is my understanding that with section A removed this has been replaced with 6 questions worth up to 10 marks each so still total 60 marks available.

Having looked at a paper with my DC they would have naturally spent a disproportionate amount of time on Section A so I can perhaps see how this has come about - it does seem connected with more competition, coaching and practice as I can also see that back in the day section A was an opportunity to score some definite points, especially useful for younger kids who may not be able to present rigorous solutions to section B questions.

Does anyone have any idea why UKMT have omitted Section A all together yet keeping 6 questions for the 2 hour paper? Surely that would give them more time to work on each question. Did they find that in previous years not enough participants were able to work on Section B?

Huge congrats to your daughter scisso!

My DD is Y7 and also got a gold and through to Kangaroo. No Olympiads in her year group but one in the year above her I think. They don't do any prep in school for JMC but she does Parallel Academy and did two past papers as part of that (plus they often have a JMC style question in their homework) so she had a bit of prep with Parallel.

Until the posts above I didn't realise girls were so unrepresented. There is probably some aggregation going on where small cohorts of high achieving boys are together in the same school and they push each other higher and learn from each other. For girls this seems less likely to exist. I also think girls schools while seemingly promoting Maths, STEM, etc, perhaps dont follow through on it enough.

I expect your probably right on approach too, some will be heavily prepared for it, while others wont be.