*4.3. E*ff*ects of Classroom Lighting on Student Performance*

Improving student progress is vital to a nation's competitiveness. Scientific research shows how the physical environment of classrooms influences student progress. The structural facilities of buildings have a profound influence on learning. Inadequate light, noise, poor air quality, and poor heating in classrooms are factors known to be relevant to poor student progress. Students exposed to more natural light (i.e., daylight) in their classrooms perform better than students exposed to less natural light [94]. Cheryan et al. [95] conducted a study of more than 2000 classrooms in California, Washington, and Colorado, in which they found students who were exposed to a large amount of daylight in their classes had better reading and math test scores than students who were exposed to less daylight in their classes (2–26% higher, depending on school district), even after statistical control of the student population that included race and socioeconomic status [96]. According to the National Center for Education Statistics (Alexander and Lewis, 2014) [97], 16% of schools with permanent buildings and 28% of schools with temporary buildings (i.e., portable) have unsatisfactory or very unsatisfactory natural lighting. Although the incorporation of natural light can be beneficial, it should be done with care to avoid visual discomfort [95].

Choi et al. (2014) [98] investigated the relationship between indoor environmental quality (IEQ) in university classrooms as a whole and student outcomes, including satisfaction with IEQ, perception of learning, and course satisfaction. The results were collected from the students.

Lighting conditions have always been an important IEQ criterion, including the sources of natural and artificial ambient and task lighting. Each of these elements has a unique role in user experiences within the built environment. Exposure to various types of light may be associated with psychological responses to human performance. Studies conducted in elementary school settings found a positive and significant correlation between the presence of daylight and student performance across three different school districts. Daylight received through skylights has a positive effect on students in their classrooms. Subsequent studies comparing classrooms with a large amount of daylighting with classrooms with less daylighting showed a 21% increase in student performance [96,99,100].

López-Chao et al. (2020) [101] state that empirical research has shown the influence of architectural spatial variables on student performance. Their article explored the relationship between the learning space and mathematics and artistic activities in 583 primary school students in Galicia (Spain). For this study, the Indoor Physical Environment Perception scale was adapted and validated, and utilized in 27 classrooms. The result of this exploratory factor analysis evidenced that the learning space has three structural categories: workspace comfort, natural environment, and building comfort. Sick building syndrome (SBS) shows that poor quality environments harm the health of users. Specifically, students perform better in brighter classrooms. Similarly, young children can differentiate their lighting needs according to the task at hand, while visual comfort is a key element for artistic activities, especially for drawing.

Heschong [96] included a focus on solar lighting as a way to isolate daylight as a source of illumination, and separated the effects of illumination from other qualities associated with light entering through windows. In this project, the author established a statistically convincing connection between daylight and student performance, and between lighting and retail performance. The author analyzed test score results for over 21,000 students from three districts located in Orange County, California; Seattle, Washington; and Fort Collins, Colorado. The author reviewed architectural plans, aerial photographs, and maintenance records, and visited a sample of the schools in each district to classify the daylighting conditions in over 2000 classrooms. Each classroom was assigned a series of codes on a simple 05 scale indicating the size and tint of its windows, the presence and type of any skylighting, and the overall amount of daylighting expected.

Kuller and Lindsten [102] are private investigators who followed the health, behavior, and hormone levels of 88 8-year-old students in four classes over the course of a school year. The four classes had very different daylight and artificial lighting conditions: two had natural light while two did not, and two were illuminated with warm white light emitting fluorescents (3000 K) while two had very cold white light emitting fluorescents (5500 K). The researchers found a significant correlation between daylight level patterns, hormone levels, and student behavior, and concluded that the practice of having no windows in classrooms should be abolished.

Wilkins (2002) [103] analyzed the performance of primary school classroom lighting given the impact that natural light has on the educational experience of students. Boyce [104] and Dudek [105,106] showed that natural light increases productivity, positively affects human performance, and has biological effects on the production of the hormone cortisol, regulating light-dark cycles, and the ability of students to concentrate. Ultimately, this is a relevant environmental aspect to be studied in order to understand the results of daylighting of different environments.
