Would they have sat some kind of mock paper?
They may have sat a GCSE paper, but that would usually be a complete waste of time in Y9 as they wouldn’t have studied nearly enough of the course (if doing 3 year GCSE) to have a decent stab at a paper plus it would be time-consuming, kids can have 20-odd exams in the real thing. They either have sat an exam made up by the school, or a commercially produced exam. These exams may have had grade boundaries made up for them, but whoever has made them up has just had a guess, that may not even be educated.
We recently made up grade boundaries for a Y10 maths exam. They didn’t sit a full GCSE paper, just what they had been taught. We looked at the results and had a reckon about where the different groups should be at the end of Y11, then stuck a pin in the results at the points that would make the grades come out ‘about right’. Then we used these as predicted grades for their report, sticking in + and - according to where our gut instinct suggested kids could do better or had got lucky. There might be kids in my group who came out with a 7 but I had them mentally pegged as better than the other kids who got a 7 so I’d give them a 7+.
That’s for Y10, and for maths where we already have a set of results, and where the kids are set so we know what results different groups of kids should be coming out with, and I’ve got years of experience. Other subjects will be stabbing in the dark.
I could give you a cautionary tale about grade boundaries for new GCSEs - PIXL, a massive commercial company that lots of schools subscribe to for teaching support, set a Y10 exam for maths before the new GCSE had been sat. Thousands of pupils across the country sat the exam and we all typed their results into a database. PIXL then analysed the results and assigned grade boundaries to the exams to give schools an idea of the grades pupils were headed for. Schools were desperate for this information and it was thought that with thousands of results pooled, PIXL could use the pegging of grades to proportions of previous years getting C+ and A+ to assign accurate grade boundaries to the exam - a bit like the exam boards will be doing to the real GCSEs.
When PIXL released their grade boundaries, experienced maths teachers were rolling in the aisles. They were laughably wrong, way too low when applied to their classes. Unfortunately there’s a shortage of experienced maths teachers and some schools believed these grade boundaries and gave them to their pupils, used them for school data analysis etc. When the actual GCSE results came out, these schools were totally in the shit, way fewer kids passed maths than they expected based on the PIXL grade boundaries. What PIXL hadn’t taken into account was the profile of schools that sign up to PIXL do not match the national picture, they are more likely to be struggling comps than leafy grammars, so the proportions of grades shouldn’t match the national picture at all.
Basically, a massive commercial company which presumably hires well-qualified people spent weeks analysing thousands of pupil results and came up with grade boundaries that were a pile of rubbish.
So take any predictions for the new GCSEs with a massive pinch of salt, just in case!