As for students who cannot understand what their teacher is teaching, there are many reasons behind this. Differences in student achievement within a class can be excessive, possibly due to the normal class grouping adopted by junior high schools nowadays. Within a class, a bimodal pattern is commonly found: teachers usually teach at an intermediate level, resulting in the students at the two extremes not benefiting.
以「聽不懂老師教的」這件事來說，背後有許多原因，可能因為目前國中採常態編班，一班內學生程度差距過大，不是很好就是很差的「雙峰現象」普遍存在，而老師通常取中間程度教課，結果落得兩頭不討好。