With Russian troops on the offensive, Ukraine's second-largest city is taking the drastic step of moving classrooms for primary and secondary education underground.

Before the war, the first day of school in Ukraine was a joyous celebration. As nearly 4 million students return to school this month, children and educators are desperate for a sense of normalcy.

As residents return to a liberated town near Kyiv, a teacher and her high school students recount what it took to survive the war.