This is what happens when planning in an economy is left up to price signals rather than actual scheduling.
You get cycles of
High commodity price -> High investment -> High production -> Low price
And the frequency of the cycle is largely based on the time it takes to go from investment to production (so 4-6 years for college graduation).
In any rational economy, the number of seats available at colleges would have been pre-proportioned based on projected future demand given the economic plan.