I would strongly advise any of you who are in any doubt about what subjects you take to go back and read this entire thread, not just the last page or two.
I can assure you all that the standard of maths and physics required for the ATPLs is easily within the capabilities of anyone who has decent results at GCSEs. For those who really struggle with Maths and Physics, even at GCSE level, the major ground schools operate refresher courses to bring your knowledge up to the standard required.
No wannabe should feel pressured into taking Maths and Physics at A-Level. With the exception of, if I recall correctly, one sponsoring employer in the relatively recent past, these subjects are not required to secure employment (though they are often required at GCSE level). Neither are they necessary for successful completion of the ATPL ground exams. By all means, if you find Maths and Physics interesting, go and do them at A-Level - but don't expect to find yourself challenged by the standard required by the ATPLs! If your preference is for French and History, go and do these subjects. An employer will be far more impressed by good passes in subjects you enjoy than by a scraped pass - or, worse, a fail - in subjects you detest.
Because of their somewhat peculiar format, the ATPL ground examinations are a hoop to be jumped through, nothing more. They are heavy going, but not particularly difficult. They should not influence or determine your academic choices.
Scroggs