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RedMaple wrote:
do I assume that the appeals panel have limited knowledge of the School?
They may or may not. Impossible to generalise, although at least one panel member will have a background in education.
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Would this mean evidence including lots of screenshots from the School's website, relevant sections of OFSTED and GCSE results etc?
Don't overload the panel with too much printed material such as Ofsted and GCSEs. Sometimes it's better to quote just one or two sentences and then wave a copy of the official report at them, saying "I have a copy here if anyone should want to verify it."
If the grammar school itself is promoting one of its strengths in the prospectus, it's worth a mention, although of much greater importance is the evidence that your son would benefit from what is on offer.
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Also, taking note of all the advice not to be critical of the allocated school, how can I show the GS is stronger in these areas than the allocated school, without being critical?
If the allocated school is non-selective, wouldn't one expect the grammar school to be stronger?
I'd be much more comfortable with an argument such as courses that are available at the GS but not at the allocated school. Again, what matters is the evidence of why this is very relevant and important for your son. Vague assertions such as "he likes the subject" are unlikely to be sufficient.
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2. We don't have medical or other evidence for underperformance on the day. DS is a worrier and felt under lots of pressure (elder sister is at GS (the one next door), us parents, two grandparents and all four blood-relative uncles and aunts all went to grammar schools) and despite lots of reassurance from us, he was very stressed just before the test. His time management was poor and he only properly finished 1 of the 7 sections. From what he's said, he only answered 3/4 of the questions in each section properly and shoved a line in the multiple choice boxes in the last 30 seconds of each timed section.
Keep it minimal. Focus briefly on sibling pressure in your written submission.
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Are the panel likely to be sympathetic to the idea of stress here?
They might be, so long as you don't overdo it with uncles and aunts!
Feeling under pressure to do as well as an older sibling might be accepted. Also the pressure of parental expectations ("despite reassurances from us"). Unfortunately these things are difficult to prove. What might really help is a letter from the current school confirming that he is indeed "a worrier", and appeared especially stressed at the time of the test.
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Plus do they have access to the answer sheets which could corroborate what he says happened?
Normally no - but appeals in your area, if it's Glos., might be an exception.
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3. He did not qualify for the undersubscribed school. There is part of me that thinks that we could appeal there on non-qualification and stand a really good chance of getting in as they are so far off their PAN, but I cannot bring myself to do it, just to get any grammar school place, as he really wants the other school. This second GS was just not on our radar, more distance but we could get there, we haven't visited it - and my gut feel is that appealing would undermine the validity of us wanting the preferred school. Is this mad?
It might show commitment, but I agree with DC17C that you shouldn't limit your options in this way (if you really would prefer the other grammar school to the allocated school).
Most appeal panels are used to the fact that parents need fallback positions, and are appealing for more than one school.
Of course, if you were to turn up at an appeal for the other school, and seemed very lukewarm about it, it might not be very productive.

It helps to appear enthusiastic/desperate!