Here is how it worked, for the inquiring minds. During Stalin's times, the education system went as follows: - nachalnaya shkola ("beginner" or elementary school): grades 1-4 - nepolnaya srednyaya shkola (incomplete secondary): grades 5-7 - polnaya srednyaya shkola (full secondary): grades 8-10 Grade 4 was required minimum for rural areas, grade 7 - for urban areas. Grade 7 graduates were free to continue education in 2 year tech/trade schools and become blue-collar professionals. Only polnaya srednyaya shkola gave an HS diploma and allowed the graduate to apply to college. I dont remember when the system was changed off-hand, but by the time I started school in late 1970s, nepolnaya srednyaya shkola was extended to grade 8 and became the mandatory minimum for both urban abd rural areas.