Assume you are a secretary of education in a country facing serious labor shortages. 
The Dear Leader has already ordered a closure of all unnecessary fields, 
which includes everything beside STEM (Science, Technology, Engineering, and Math), Medicine & Accounting.
Now it's your job to trim years from primary & secondary education.

What's the maximum number of years that you could trim from the current 12 (8 primary, 4 secondary) without sending unprepared high school graduates to college?