This is the 2024th most frequent Russian word.
школьников
"Schoolchildren."
The word 'школьников' here is in the genitive plural form, used to indicate the students who are seen during the break.
На перемене школьников можно увидеть на школьном дворе.
During the break, students can be seen in the schoolyard.
Here, 'школьников' is in the accusative plural form, denoting the direct object (students called by the teacher).
Учитель призвал всех школьников в аудиторию.
The teacher called all the students to the auditorium.
In this sentence, 'школьников' is in the genitive plural form, showing possession (the backpacks belonging to the students).