Honestly, as a regional student, I didn't know SEHS's were a thing until after I finished Year 12. I assume they're stream-based, such as a science-focused school, maths-focused schools too. No teachers, parents or students mentioned it, I never saw posters or advertisements either. I'm sure there would be some kids who might have known, and maybe considered applying for these schools, but it would be tricky to get kids from regional areas to relocate to Melbourne for a high-level secondary school.
Oh well