after the (final/end of year) exams, there is a different lesson schedule
at high school, after the end of year exams, the usual schedule changes and we have a period of special lessons
for example, we have special lectures from teachers from outside the school, classroom cleaning time, homeroom, and so on. Often, school finishes early during this period.
「テスト後」＝ after the tests / after the exams
「期間」＝ period
「特別授業」＝ special lessons / special classes / different lesson schedule
「テスト後の特別授業の期間」＝ after the tests, there is a period of special lessons / after the (final/end of year) exams, there is a different lesson schedule
「高校で、学年末テスト後の、通常授業とは異なる、特別授業の期間。」＝ at high school, after the end of year exams, the usual schedule changes and we have a period of special lessons
「例えば、外部講師による講演、清掃活動、ホームルーム活動など。通常と違って、午前中だけや短縮授業が多い。」＝ for example, we have special lectures from teachers from outside the school, classroom cleaning time, homeroom, and so on. Often, school finishes early during this period.
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