It seems to me this highlights quality issues in elementary schools more than pre-K, and indicates longer-term success must connect pre-K with all the other issues related to educating a child.
Recent research in the U. K. has revealed that we, as a society, may be dangerously over-reliant on GPS tech, and Japan may suffer long-term mistakes caused by GPS mis-navigation.
And we've used a relatively simplistic term called neutron Multiplication Factor which is the K that if the K equals one the neutron population is steady as is the fission rate.