Covid Closed the Nation’s Schools. Cleaner Air Can Keep Them Open.

An open window in a classroom at East High, one of Denver’s oldest public schools. A coronavirus outbreak that began in November 2021 sickened more than 500 students, and one staff member died.

Scientists and educators are searching for ways to improve air quality in the nation’s often dilapidated school buildings.

Ukraine Is Still Grappling With the Battlefield Prigozhin Left Behind

A makeshift memorial for Yevgeny V. Prigozhin in Saint Petersburg, Russia, on Friday.

He shored up Russian forces at their most vulnerable and drew Ukraine into a costly fight for Bakhmut, giving Moscow time to build defenses that are slowing Ukraine’s counteroffensive.

In Push to Modernize Cairo, Cultural Gems and Green Spaces Razed

The Egyptian government has demolished historic tombs, cultural centers, artisan workshops and gardens in pursuit of large-scale urban renewal.

Bob Barker, Longtime Host of ‘The Price Is Right,’ Dies at 99

The winner of numerous Emmy Awards, he was almost as well known for his advocacy of animal rights as he was for his half a century as a daytime television fixture.