You've obviously been through a dreadful time, and my heart goes out to you, but I would be less than honest if I didn't say that you will need a very, very strong academic case to win an appeal.
You mention a predicted level 5 for English and Maths. Does this mean Science will be only a 4?
Whilst agreeing with just about everything Sally-Anne has so helpfully written, I very much doubt whether any appeal panel would accept the results of practice papers as evidence. They have not been officially marked and standardised, and as Patricia has mentioned elsewhere, the same practice papers have been used for years and years, and taken home, so no one can ever be sure who has had sight of them in advance.
If you haven't already done so, have a look at section B24 on the following page:
http://www.elevenplusexams.co.uk/11plus ... nswers.php
One thing missing from my list, that could be used as evidence, would be good school reports, especially
if they indicate very high
achievement. (Unfortunately some school reports these days hardly mention achievement
, as if it's politically incorrect to do so!