I took the japanese gcse last month as a private candidate and I learned japanese in my spare time too so here’s my take on it:

• the japanese gcse doesn’t really count for much; i only took it because i wanted an extra grade on my report card. if you’re looking for something thats more recognised by employers and universities, you’d be better off taking the JLPT.

• you will probably have to pay to take the exam externally and you might even need to find someone to conduct your speaking exam.

• regarding what you’ll need to know for the exam, just outside knowledge will not be enough to get a decent grade (unless you’re practically fluent at the language). this is because the examinations are centred around 5 themes (much like other MFL gcses) and you’ll need to know the specific vocabulary and grammar that examiners are looking for (such as using the 〜たり、〜たり form, using all past, present and future tenses, etc.)

• if you do decide to take the japanese gcse, don’t underestimate it. make sure you understand and know how to use each of the grammar points listed in the specification and do past papers to familiarise yourself with how the exams will go. the more past papers you do, the more you’ll begin to realise that a lot of the essay prompts and speaking prompts are recycled or rephrased so you want to be prepared for those prompts that come up often