First graders attend the opening ceremony of the new school year in Sofia, Bulgaria, Sept. 15, 2022. A new school year kicked off in Bulgaria on Thursday.(Photo: Xinhua)

Students enter their school in Sofia, Bulgaria, Sept. 15, 2022. A new school year kicked off in Bulgaria on Thursday.(Photo: Xinhua)

Students enter their school in Sofia, Bulgaria, Sept. 15, 2022. A new school year kicked off in Bulgaria on Thursday.(Photo: Xinhua)

Students wait to enter their school in Tunis, Tunisia, on Sept. 15, 2022. Tunisian primary and secondary schools opened on Thursday. (Photo: Xinhua)