New research has tentatively reconfirmed earlier findings that simply installing commercially available $700 air filters in classrooms that were void of any noxious fumes to begin with raised math scores by 0.20 standard deviations and English scores by 0.18 standard deviations! These are shocking, large, permanent improvements that are cheap, easily scalable and equal to cutting class size by one-third, and almost as large as the KIPP charter school network!