Higher speech levels in K-12 classrooms correlate with lower math achievement scores

Abstract

Sound levels in 275 K-12 midwestern classrooms have been logged every 10 s over two occupied school days (220 rooms over the 2015–2016 and 2016–2017 academic years) or four occupied school days (55 rooms in the 2017–2018 academic year). Measurements were made two or three times to capture data during both heating and cooling seasons. K-means clustering was used to group the data into times when speech was or was not occurring; then acoustic metrics were calculated from the clustered data. Demographic data and achievement data in the form of percentile ranks on math and reading tests were also collected for the students in each classroom and aggregated into classroom averages. Multivariate linear regression analysis on the initial dataset of 220 classrooms indicates that higher speech levels in classrooms correlate with lower math scores, with a significant interaction with the percentage of students receiving free or reduced-price lunches in the classroom. A statistically significant interaction is also found of non-speech levels and the percentage of gifted students in the classroom on reading scores. Data from the latter 55 classrooms are used to cross-validate the initial model. [Work supported by the United States Environmental Protection Agency Grant No. R835633.]