I would like to say: "But then it turned out that he doesn't even have a secondary school qualification."
I am not sure how to say "to turn out", as my dictionary provides a lot of words for that. In this context which word should I use?
The requirements for each certificate may vary from state to state, but usually the first is what you get for suceeding at the last year at the Hauptschule (in states that have it) or by finishing your year at one of the other schools. The second you get for successfully finishing Realschule or finishing your year at the Gymnasium. The Fachhochschulreife is obtained by going to a Fachhochschule for those without the Allgemeine Hochschulreife you get for successfully finishing your last year at the Gymnasium and your Abitur exams.
First, something like that in English would normally be referred to as “a high school education/diploma” because in this case “qualification” is not something you are likely to hear.
It’s obviously not that easy to translate the basic term “secondary school education/diploma” directly into English, given the different alternatives and variations in the German educational system.
As you have pointed out, there are a few “equivalents”; and it’s difficult to express that as accurately as possible in one general term in English that would include all the German alternatives to the basic, simpler English (American) one.
That’s why I was thinking maybe even Highschool-Abschluss/High-School-Abschluss would, in fact, be better if someone actually had the American educational system in mind.
So I guess that best term to use is Hauptschulabschluss although Hauptschule—this particular school you attend after the Grundschule—might be understood as a more specific term in the German system (5th to 9th/10th grade). After the Grundschule the educational system there branches off in several quite different, specific directions; around 5 or 6, I believe.
That all I was trying to make clearer. Thank you for responding and helping to clarifying this.