One in six Americans spend their days in a classroom, putting them at risk of breathing in air pollutants — which are two to five times higher indoors than outdoors, according to the American Lung Association. A team of Boston University students is working to fix that. Senior Primah Muwanga and junior Ellen Zheng, along with recent graduate Celine Chen and faculty advisor Thomas Little, won the 2025 Janetos Climate Action Prize in May for designing sensors that test air quality differences between buildings across BU’s Charles River Campus.