国际教育成就评价协会（IEA）：八年级预期、实施和实现的数学和科学课程-2023年国际数学与科学评估结果报告（英文版）

Opportunity to Learn (OTL) is one theoretical framework that can be used to examine relationships among the intended curriculum, the implemented curriculum, and student achievement.15,16,17,18 There is no single definition of OTL, and it is sometimes considered to be quite expansive, encompassing factors such as content coverage/or exposure, instructional quality, time on task, teacher quality, and resources. An important aspect of OTL is content coverage across different levels of the curric