I don't know about you but, my CV is one page long so it just does not have enough space to list every single grade that I have achieved in non aviation related areas during the course of my life. All that space is reserved for the details of all my FLIGHT experience, ratings, licences and QUALIFICATIONS.
However if GCSEs is the only thing you have ever achieved, by all means fill the space on that page with the grades that you got in all the different subjects, you could also list your after school activities, Duke of Edinburgh award, scouts etc. Im sure thats the sort of stuff that will really make all the difference
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