This is the 6415th most frequent Russian word.
школьных
"Школьных" means "school-related" or "of schools" in English.
Here, 'школьных' is an adjective in the genitive case, modifying 'годах' to indicate the specificity related to school.
Мы обсуждали воспоминания о школьных годах.
We discussed memories of the school years.
In this context, 'школьных' functions as an adjective in the genitive case describing 'программ' to denote their connection to school settings.
На собрании говорили о проблемах школьных программ.
At the meeting, they talked about issues in school curriculums.
In this sentence, 'школьных' is used as an adjective in the genitive case, modifying 'парт' to describe its belonging to school.