On the morning of the first school day this year, my son's form teacher surprised all parents of the class with her WeChat post of a sleek, new air purifier in the back of the classroom.

Thank-you messages, tearful faces, thumbs-up, flowers and other happy icons soon flooded the mobile forum. One mother said she was leaping with joy, and another claimed it was the best gift she had received for the Chinese New Year.

Then a father asked the teacher to turn the air to full blast, bringing to our attention the fact that it was a compact, family-use filter, which many smoggy days ago we had offered to donate by "putting together one day's or two days' lunch money", as one parent suggested.

Yet we cannot complain, despite our doubts about its effectiveness and potential side effects.

Until that day, we'd assumed our pleas for air cleaners in classrooms as a quick fix to smog shrouding the city had fallen on deaf ears. Education authorities had worried about electrical safety, ventilation in a sealed space and costs. Social equality was also a concern if schools accepted donations from well-off parents.

When smog came, hapless parents prayed it would either leave soon or hit harder so schools would be shut down. The recent recurring episodes of air pollution had unnerved the most tough-minded residents caught in days of a sullen, yellowish sky that foreboded more bouts of pollution.

In desperation, some felt it irritating when the National Museum of China invited the public to "evade smog" in its halls equipped with state-of-the-art filtration systems.

While roadside pollution levels soared to dangerous levels, the cavernous museum had tamed PM2.5, the dreaded small, harmful particulate matter in the air, through a combination of air purifying, conditioning and ventilation technologies.

Not everybody would agree to compare a museum with a classroom in terms of air-quality standards. But the different priorities about the past and future touched a raw nerve when people thought museum visitors and exhibits could have a breath of fresh air, but schoolchildren couldn't.

It also reinforced the public perception that the smoggy air could go away, if we wanted it to, like what happened during the 2008 Beijing Olympic Games and the Asia-Pacific Economic Cooperation meeting a couple of years ago.

So we heaved a collective sigh of relief at the sight of the modest purifier, which would be soon improvised in schools and kindergartens in the city after a milestone decision by education authorities.

Simple and naive it might sound, I've made a New Year's wish that this will be just the beginning of a series of efforts by educators and parents to bring fresh air into the classroom.

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