ile:有趣除法之除法典型应用、除法算式谜03.mp4 file:巧数图形之图形计数、分类思想05.mp4 file:有趣推理之推理小故事、图文算式04.mp4 file:数学家小故事05.mp4 file:数一数和算一算（速算与巧算，找规律写数）04.mp4 file:动手操作之切割、对折、移多补少问题03.mp4 file:图形的等积变换03.mp4 file:有趣乘法之简单算式谜、变加为乘03.mp4