Jiri Lonsky Apr 13, 2018:

It really depends on your audience ... ... so it would be good to know if you are translating into UK or US English. So far as I know, there are no comparable institutions in the US, except maybe some private schools. The model prevalent in the public sector is a separate "Junior High School", covering mostly grades 7 and 8, but in some cases also 6 (and in the past even 9), followed by "High School" (or "Senior High School") for higher grades covering the legally required length of education. So far as I know, the UK equivalent of Junior High is called most often "Middle School".