Of course this was ignored. The idea of an economic zero-sum game is an old one, and it was refuted by economists centuries before Julian Simon. While the teacher avoided any such pronouncements, of course, kids are smart, and they might easily have read in that clear subtext. In that sense, when the alarmist crowd successfully gets its ideas into the schools, it is preaching to the damned. It is trying to indoctrinate the very symbols of its own failure.
Young people are sensitive to hypocrisy.
That may be the best defense. But, thanks to Julian Simon, in future it may not be the only one.