She advised to focus on his desire to study science as he wants to be an engineer.
Not sure what this has to do with qualification for grammar school.
She also said to emphasise attributes such as independant learner, maintaining academic level whilst undertaking all other sporting/music activity, competitive/driven nature.
Worth a brief mention, provided you don't go into details of sports, etc.! (Grade 3 violin might be worth mentioning, though, if it included theory.)
Any thoughts what I'm missing?
Have you ticked off the items in our list of academic evidence?http://www.elevenplusexams.co.uk/appeal ... cation#b11
You shouldn't have to write much - the evidence should speak for itself.