Clean Air for Schools is supporting the development of the next generation of quiet air purifiers designed specifically for classrooms, advancing adoption in schools and districts with the highest rates of absenteeism, and advocating for supportive policies at state and federal levels.

The Problem

We've lived through a pandemic that fundamentally shifted our understanding of airborne transmission and the importance of indoor air quality, yet fifty million American students spend half their waking hours breathing poor-quality air that impairs their ability to learn. When children get sick at school, they bring illnesses home, causing 98 million lost parent workdays and cascading economic impacts. And fine particulate matter air pollution hits hardest in low-income schools, which are disproportionately located near highways and industrial facilities. This problem replicates across the globe with even worse outcomes for children in the most polluted cities.

The Solution

Our three-pillar approach to developing and deploying the next generation of air filters in every classroom:

1. Device Development & Standards: Create open-source designs for quiet (<40 dBA), powerful (750+ CFM), affordable (<$2/student/year) classroom air purifiers, solving the fundamental problem that standard commercial units are too loud, underpowered, and expensive for sustained global classroom use.

2. Evidence & Implementation at Scale: Deploy strategic programs in high-need districts to demonstrate reductions in absenteeism and improvements in student performance while providing hands-on implementation support to drive adoption.

3. Policy & Financing Infrastructure: Advance state clean air legislation, establish new public funding mechanisms, and create procurement pathways that make adoption inevitable rather than optional.

Scale Potential: The U.S., for example, has 13,500 school districts, but they follow a near power-law distribution: just 2% of school districts (~250) serve one-third of all students. By focusing on these large urban districts first, we can protect 25 million students while building proof points for broader adoption both within and outside school systems.

The evidence is growing that improving air quality can specifically improve student outcomes, but school systems don't yet know it. Just as school lunches are accepted as foundational for student attendance and focus, air filters can boost performance and reduce both student and teacher absenteeism for only a few dollars per student per year:

• When a gas leak forced installation of air purifiers in California schools, math scores jumped 0.20 standard deviations and English scores 0.18—equivalent to the gains from expensive class-size reduction but at less than 1% of the cost ($30-50 per student vs. $7,000)

• When Swedish daycare centers installed air cleaners, illness-related absences plummeted by 55%.

• A recent randomized controlled trial found that air purifiers cut student absenteeism by 12.5%, with even larger effects for students with higher starting rates of absenteeism.

• Improving ventilation and removing mold in schools led to meaningful gains in English and math scores as well as pass rates

• Israeli students performed worse on high-stakes exams when air pollution spiked on test day.

• Similar results were found in China.

• In a study of 3000 schools in China, drops in air quality have been found to increase daily absence rates.

• Just two hours of breathing filtered air improved executive function scores.

This is the right time to work on this.

Despite strong evidence that air purifiers protect students from both pollution and infectious disease, adoption remains minimal:

• Many school systems purchased devices during COVID but have since turned them off or discarded them, viewing clean air as a pandemic-era emergency relic

• Commercial air purifiers are too loud (teachers won't use them), underpowered for large classrooms, and too expensive for sustained adoption

• There is no coordinated effort to advance clean air policies or help districts implement evidence-based interventions

• The benefits—higher test scores and reduced absenteeism—remain niche academic topics not yet translated into effective communications for decision-makers

We are sitting at a critical window where we’ve lived through a major paradigm shift around clean air but haven’t yet adapted to match the cutting edge scientific understanding of both the problem and solutions.

The Impact Across Education, Health, and Biosecurity

1. Education: Reaching 10 million students by 2030, we will prevent millions of absence days and boost test scores for just a couple dollars per student per year.

2. Child Development: By reducing classroom PM2.5 for millions of children during critical developmental windows, we can enhance acute cognitive function in school, support healthy brain development (fine particulate exposure is believed to directly cause drops in IQ), and protect future earning potential.

3. Biosecurity: By establishing air quality infrastructure across thousands of schools where children drive community transmission, we create distributed pandemic defense that operates year-round against both seasonal and novel airborne pathogens—protection that exists before outbreaks occur, unlike emergency measures deployed only during recognized crises.

Leadership

David Carel uniquely combines education entrepreneurship with airborne disease expertise. He

• co-founded Panorama Education (Y Combinator), which serves tens of thousands of schools nationwide

• scaled early literacy interventions with the South African government through Funda Wande.

• co-led Blueprint Biosecurity's efforts to accelerate humanity's ability to prevent and mitigate airborne pandemics.

David received Bachelor’s degrees in Economics from Yale College and in Philosophy, Politics, and Economics from the University of Oxford on a Rhodes Scholarship.