During World War II, the U.S. Army taught typing in rooms so large that the instructor–a non-certified soldier-teacher–used a microphone, and students listened on headphones.
A public school not only could do this, at least one has. In the 1960s, a high school in Melbourne, Florida, adopted this methodology. Then-principal B. Frank Brown reported that one typing teacher had 125 students per class, five classes per day, for a daily student-load of 625.
“The surprising thing is that we never thought of this before,” said Brown. Other high schools still haven’t thought of it.
Similar consolidation could be achieved in classes in which the teacher lectures to students–still the most common teaching method. For example, a high school teacher may present the same lecture to six classes of 25 students every day. If, instead, the teacher lectured to the 150 students as a group, the teacher would have five periods available for other purposes.