BOISE, Idaho — When the sky over Boise turned a dull orange one morning last September, teachers at Cottonwood Elementary didn’t need to wait for an announcement. A small air quality monitor on the school’s front wall had already turned red, and recess was moving indoors for the third time that week.
Across the western United States, wildfire smoke is increasingly shaping the school calendar. A survey by the Western Schools Health Alliance found that 61 percent of districts in nine Western states had canceled outdoor activities or closed buildings because of smoke at least once in the past two school years, up from about a third five years earlier.
“Smoke days are becoming as normal as snow days in some places,” said Dr. Renee Calloway, the alliance’s research director. “The difference is that smoke can last for weeks, and it often comes right at the start of the school year.”
Filters, monitors and new rules
Districts have responded with a mix of upgrades and policies. Many have replaced older ventilation filters with higher-efficiency ones, added portable air purifiers in classrooms and installed air quality monitors outside schools. Some have adopted clear thresholds that determine when students stay indoors or when athletic practices are canceled.
- Districts canceling outdoor activities due to smoke: 61 percent
- Typical cost of a classroom air purifier: $200 to $500
- Average smoke-affected school days per year: about 6 in surveyed districts
- States surveyed: 9
In Boise, the district spent about $2.1 million over two years upgrading filtration in 48 buildings, using a mix of state and federal funds. Officials say indoor air in most classrooms now stays in the healthy range even on heavy smoke days.
Balancing health and learning
Deciding when to close schools entirely remains difficult. Health experts note that some students’ homes may have worse air than a well-filtered school building, and that closures can be hard on working parents. Others argue that students with asthma and other conditions need extra protection.
For many of our kids, the cleanest air they breathe all week is in a classroom with a good filter. Closing the building isn’t always the safest choice.
Mark Delaney, superintendent of a school district in central Oregon
Parent groups in some districts have pushed for more communication and flexibility. Jessica Huang, who leads a parent council in a Denver suburb, said families want earlier notice and clearer explanations of how decisions are made. “When we find out at 6:30 a.m. that school is closed, it’s chaos for parents who work,” she said. “We understand safety comes first. We just want a plan we can count on.”
Some districts are also adjusting their calendars. A few in California and Washington have shifted the start of the school year earlier or added flexible days that can be used for remote learning if smoke closes buildings. Others have built covered outdoor spaces with filtered air for physical education classes.
Public health researchers say the long-term effects of repeated smoke exposure on children’s health are still being studied. Dr. Calloway said schools can play an important role by providing clean indoor spaces and teaching students and families how to read air quality alerts.
At Cottonwood Elementary, teachers have turned smoke days into lessons. Fourth-graders track daily air quality readings on a chart in the hallway and learn how filters work. “They ask great questions,” said teacher Amy Chen. “Why is the sky orange? Where is the fire? Is it coming here? Our job is to keep them safe and help them understand the world they’re growing up in.”
