BRUSSELS (AP) — Thousands of students skipped school for the third week in a row and more than 30,000 swamped the center of Brussels to demand better protection of the world's climate.

What started out as a march of a few thousand high school student swelled to a vocal movement that Thursday also included many that skipped courses at university. Brussels police estimated the crowds at 32,000, who braved the cold and snowy conditions.

Another climate march — adults included — is set for Sunday. It drew some 70,000 last month.

"The planet can do without us, but we cannot do without the planet," was one of the many signs carried around.