Girls hug as they arrive to school for their first day back to classes in Minas, Cuba's Havana province, Tuesday, Sept. 1, 2026. (AP Photo/Ramon Espinosa)

School children enter an underground school on their first day back, in Kharkiv, Ukraine, Tuesday, Sept. 1, 2026. (AP Photo/Andrii Marienko)

School children enter an underground school on their first day back, in Kharkiv, Ukraine, Tuesday, Sept. 1, 2026. (AP Photo/Andrii Marienko)

Children play in an underground shelter during an air raid alarm during the traditional back to school celebrations in Kyiv, Tuesday, Sept. 1, 2026. (AP Photo/Francisco Seco)

Teachers conduct online lessons for elementary students from a public school damaged by a Russian attack, in Kyiv, Tuesday, Sept. 1, 2026. (AP Photo/Dan Bashakov)

Yevhen Yurko, 41, and his son Darii, a 6-year-old first-grader, pose for a photo in the courtyard of a public school damaged by a Russian attack, in Kyiv, Tuesday, Sept. 1, 2026. (AP Photo/Dan Bashakov) CORRECTION: Name of child corrected from Dayri to Darii.

In this image provided by Manish Maharjan, filmmaker and drone pilot Manish Maharjan operates a drone at the Rashuwaghadi hydropower project in Rasuwa district, Nepal, Monday, Aug. 31, 2026. (Manish Maharjan via AP)

In this image provided by Manish Maharjan, filmmaker and drone pilot Manish Maharjan operates a drone at the Rashuwaghadi hydropower project in Rasuwa district, Nepal, Monday, Aug. 31, 2026. (Manish Maharjan via AP)