Expanding urban air quality monitoring through school-based air quality sensor networks: the REDES+ project in Santiago, Chile

Low-cost air quality (AQ) sensors are increasingly used to expand environmental monitoring in cities, particularly in contexts where regulatory networks provide limited spatial coverage. Here, we present REDES+ (RED de EScuelas para el Monitoreo Ambiental de Santiago), an ongoing interdisciplinary research project that deploys a network of AQ sensors in public primary schools across Santiago, Chile. The project aims both to generate fine-scale environmental data and to support school-based learning activities using real atmospheric observations,  in order to investigate how environmental conditions around schools relate to student attendance and academic outcomes.

The project has installed AQ sensors in approximately 50 public schools distributed across the Santiago Metropolitan Area. Sensors provide continuous, near–real-time environmental data on fine particulate matter (PM_2.5) and air temperature at school sites, enabling the characterization of spatial and temporal variability in air pollution and thermal conditions experienced by students during the school day. These data streams are made freely accessible to teachers and students through an existing open data platform. Environmental data are being integrated with administrative records on school attendance and standardized academic performance indicators to examine how environmental exposure and absenteeism interact in shaping educational outcomes.

Preliminary analyses of the fully deployed sensor network reveal clear spatio-temporal patterns in PM_2.5 concentrations across schools, including localized pollution gradients and short-term peaks that are not revealed by air quality models relying solely on the sparse official monitoring network. These observations highlight the added value of dense, school-based AQ sensor deployments, for resolving fine-scale exposure variability within urban areas, as well as the potential impact on student attendance and learning.

REDES+ is designed as both a research and capacity-building initiative. In parallel with data collection, the project aims to develop an independent open-access environmental data platform and to engage school communities through outreach and educational activities. These activities include training sessions and hands-on workshops for teachers, focused on using the data for student-driven science projects, introducing basic concepts of air quality and data interpretation in the classroom, as well as outreach actions to promote awareness and understanding of local air quality and climate-related risks.

By establishing a school-based network of low-cost sensors, REDES+ contributes fine-scale environmental data from locations that are rarely monitored by conventional air quality stations. The project seeks to generate evidence relevant to research on environmental inequality, school infrastructure planning, and public policies aimed at promoting healthier and more equitable learning environments. More broadly, REDES+ provides a transferable framework for integrating low-cost sensing, environmental research, and education in Latin American cities.