“24时记时法”是苏教版小数教材中最难的课堂教学之一。教师竭尽全力教学,学生囫囵吞枣接受,学生课堂练习、课后作业正确率还不到一半。尤其是“24时记时法”和“普通记时法”互相转化,让许多学生伤透脑筋。巧用一一对应,能使课堂教学效率显著提高。 “24 Chronicle ” is one of the most difficult classroom teaching in the Sujiao version of decimal textbooks. Teachers make every effort to teach, students embarrassed to accept, students practice in the classroom, after homework accuracy is less than half. In particular, the “24 Chronicle” and “The Common Chronicle” transform each other, leaving many students with a headache. Clever use of one-to-one correspondence, can make classroom teaching efficiency significantly improved.