Here's Carmen Farina:
“Once I was about to visit a principal,” [New York City Schools Chancellor] Ms. Fariña said, “who told me, ‘You’re going to love coming here because you can hear a pin drop.’ I said, ‘I better not come because that isn’t going to make me happy.’ ”And here's reality:
Schools Chancellor Brings Joyful and Fierce Style
...[E]merging research suggests that quieter noises can have varied effects on student learning and memory.
Low or barely perceptible sound—be it from a lecture in the classroom next door, a heating system that keeps turning on and off, or even a classroom aquarium filter—can increase stress and interfere with memory and learning....
“You can’t depend on the kids to complain,” said Ruth M. Morgan, a speech pathologist at Ephesus Elementary School in Chapel Hill, N.C. “Kids generally go with the flow, and they wouldn’t let you know there’s too much background noise.”
How Loud Is Too Loud?
Noise is measured in decibels on a logarithmic scale; every 10 decibels marks an increase in sound that is twice as loud. Normal conversation is usually in the range of 60 to 65 decibels, and children often speak more softly than adults, as low as 35 decibels.
...In a 2013 study in the Journal of Urban Health, a publication of the New York Academy of Medicine, 8- and 9-year-old students who had higher “ambient” noise levels in school performed significantly worse on standardized tests in mathematics and French language, after controlling for their socioeconomic backgrounds. A difference of 10 decibels of regular background noise was associated with 5.5-point-lower scores on average in both subjects.
Similarly, a prior study found students were highly distracted by a television playing in an adjoining room, even when it was barely audible, but they were unable to identify why they were having trouble concentrating.
The results don’t surprise Ms. Morgan in Chapel Hill. She noticed that while the classroom didn’t seem particularly loud, both she and her students seemed to be having trouble following conversations during sessions in which students worked in groups.
“So much of class now is the children speaking to each other, doing buddy reading,” she said. “And children’s voices are softer; I was having difficulty hearing them.”
Some sounds are also more vulnerable to distortion: s-, sh-, and ch- sounds in speech are particularly easy to mistake when competing with low-frequency mechanical sounds, such as the hum of a computer fan or heating system.
Ms. Morgan said she thinks her school’s noise issues may be common in older schools, where former “open concept” classrooms were later closed in with walls that typically have less noise insulation than new construction, allowing students to hear more lectures and mechanical sounds in other rooms.
Low-Level Classroom Noise Distracts, Experts Say