Students in any grade level vary widely in their mathematics achievement, with the typical classroom including four to seven grade levels of mathematics proficiency. Due to this large range of math...

中文翻译：

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加速中学数学的地点和原因

任何年级的学生在数学成绩上都有很大差异，典型的课堂包括四到七个年级的数学水平。由于这个大范围的数学...