Dr Challoner’s Grammar School is one of the most sought-after boys’ grammar schools in Buckinghamshire, drawing applications from families across Amersham, Chesham, the Chalfonts and the wider Misbourne valley. With a Year 7 published admission number of just 180 places and consistently strong examination results, competition for a place is intense, and early preparation makes a difference.
This guide explains what your son will face: the Buckinghamshire Secondary Transfer Test, the qualifying score, the defined catchment area and the realistic targets families should be working towards. It is written for parents who want an accurate picture rather than guesswork, so that you can plan preparation that fits how selection works.
School Overview
Dr Challoner’s Grammar School is a selective boys’ school for ages 11 to 18 on Chesham Road, Amersham, HP6 5HA (URN 136419). It is named after Bishop Richard Challoner and is the sister school to Dr Challoner’s High School, the girls’ grammar in Little Chalfont. The two are separate schools with separate admissions, and confusing them is one of the most common mistakes families make.
On Ofsted, it is worth being precise. The school’s last graded inspection, in November 2019, judged it Outstanding overall. Its most recent inspection, on 5–6 November 2024, was an ungraded inspection, which does not award an overall grade. So the school remains Outstanding from its last full graded judgement, and you can read both reports on the Ofsted website.
At GCSE in 2024/25, the school recorded an Attainment 8 score of 73.9, with 96.2% of pupils achieving grade 5 or above in both English and maths (Progress 8 was not calculated for 2024/25). You can verify these figures on the DfE school performance service.
At A-level in 2025, the school reported 64.9% of grades at A*–A, 87.8% at A*–B, 26% at A*, and a pass rate of 99.9%, as published on the school’s own exam results page. These outcomes place Dr Challoner’s among the leading state schools in the region and explain why demand for places is so high.
The Entrance Exam: Buckinghamshire Secondary Transfer Test
Entry to Dr Challoner’s Grammar School is determined by the Buckinghamshire Secondary Transfer Test (STT), the shared 11+ used by all Buckinghamshire grammar schools. The test is provided by GL Assessment and consists of two papers, each lasting around 60 minutes including instructions and practice examples.
Across the two papers, your son will be tested on verbal reasoning, English (comprehension, grammar, punctuation and spelling), numerical reasoning and maths drawn from the Key Stage 2 curriculum, and non-verbal and spatial reasoning. Answers are recorded on separate multiple-choice answer sheets, so accurate transfer of answers and steady timing are skills in their own right.
Because the same test serves every Buckinghamshire grammar, preparing for the STT prepares your son for Dr Challoner’s specifically. What differs between schools is not a separate exam, but the score achieved and how each school’s oversubscription criteria are then applied.
Pass Mark and Realistic Score Targets
In Buckinghamshire, the qualifying score is 121. A standardised score of 121 or above means a child has “qualified” for a grammar school place. The standardisation process adjusts for a child’s age in months, so younger pupils are not disadvantaged against older ones in the same year group.
121 is the threshold to qualify, not a guarantee of a place at any particular school. With a published admission number of 180 and high demand, Dr Challoner’s regularly receives more qualifying applicants than it has places. When that happens, places are allocated by the school’s oversubscription criteria rather than by score.
So families targeting Dr Challoner’s should aim comfortably above the minimum. A child who is consistently scoring around 125 or higher in realistic, timed practice papers in the months before the test has a sensible buffer above 121 to absorb the natural variation of exam day. Treat 121 as the floor, not the goal.
Key Dates for September 2027 Entry
For entry in September 2027, the Buckinghamshire registration and testing timeline is as follows:
- Registration opens: 10am on Friday 1 May 2026
- Registration deadline: 3pm on Tuesday 2 June 2026
- Test dates: 8 and 10 September 2026
Children attending a Buckinghamshire state primary school are usually entered automatically, but families whose son attends school outside the county must register directly with Buckinghamshire Council within the window above. Missing the registration deadline is final, so put these dates in your diary now. The school also runs admissions open events; check the Dr Challoner’s website for current open evening dates, as these are confirmed each year.
Competition and Catchment
Dr Challoner’s Grammar School admits 180 boys into Year 7 each September, and it operates a defined catchment area. Once qualified children are ranked, priority within the oversubscription criteria gives weight to children living inside the school’s catchment, which covers Amersham, Chesham, Chalfont St Giles, Gerrards Cross, Great Missenden, Prestwood and the surrounding area.
This matters for planning. Two boys can both score above 121, but the one living within the defined catchment will generally be in a stronger position than one applying from outside it. Families on the geographic edge should think carefully about realistic chances and apply to more than one grammar to spread risk. The full, current admissions and oversubscription details are published in the school’s admission arrangements, and you should read them alongside this guide rather than relying on memory of previous years.
Preparation Timeline and Strategy
The strongest results come from starting early and building gradually rather than cramming in Year 6. Ideally, preparation begins in Year 4, when there is time to grow vocabulary through wide reading, strengthen mental arithmetic, and introduce reasoning puzzles in a way that feels enjoyable rather than pressured. Year 5 is then the period for learning each question type properly and moving towards timed practice, with the final stretch in early Year 6 focused on full papers under exam conditions.
A principle we use at Think Smart Academy is to prepare the four subject areas separately, verbal reasoning, English, maths and non-verbal reasoning, so that no weakness is hidden inside an overall percentage. A child can look “on track” on average while quietly losing avoidable marks in one strand, and isolating each area is the fastest way to find and fix that.
We cap our 11+ classes at eight pupils so that every child receives individual attention and feedback, rather than sitting in a large group. Preparation for Dr Challoner’s is supported from our High Wycombe centre and online, so families across the catchment can access the same teaching whether they attend in person or learn remotely.
Before committing to a long programme, we recommend booking a free diagnostic assessment. This benchmarks your son across all four areas, gives an honest projection of where he stands relative to the 121 threshold and the higher targets above it, and produces a personalised plan instead of generic advice.
Common Mistakes to Avoid
A handful of avoidable errors cost families places every year:
- Confusing it with Dr Challoner’s High School. Dr Challoner’s Grammar is the boys’ school in Amersham; Dr Challoner’s High is the girls’ school in Little Chalfont. They are separate schools with separate admissions, so apply to the correct one.
- Starting too late. The STT tests reasoning skills rarely covered in the primary curriculum, so even a top-of-the-class child needs focused preparation begun well before Year 6.
- Treating 121 as the target. With 180 places and heavy demand, aim comfortably above the qualifying score, not at it.
- Missing the registration window. Out-of-county families must register by the 3pm, 2 June 2026 deadline; there are no extensions.
- Ignoring catchment reality. Strong scores still sit within oversubscription criteria, factor your location in and apply to more than one school where sensible.
Next Step
If Dr Challoner’s Grammar School is the right fit for your son, the first move is to find out where he stands and what a realistic plan looks like.
Read more on our Dr Challoner’s Grammar School 11+ page, then book a free consultation to arrange a diagnostic assessment at our High Wycombe centre or online. Early, targeted preparation is the biggest factor families can control, and the sooner you start, the more options your son will have.