记得一位科学教师说过:“没有材料,就没有探究。”在科学课堂上,一种材料就预示着一个现象,一个情境,一项探究。对于科学教师来说,准备材料、积累材料、携带材料是工作的一部分。科学老师的行囊里总是装着科学材料和一颗与科学贴近的心。《混合身边的物质》一课用到沙子,但我们 One science teacher remembers saying: “Without material, there is no inquiry.” In science class, a material indicates a phenomenon, a situation, an inquiry. For science teachers, preparing materials, accumulating materials, and carrying materials is part of the job. The science teacher's bag always contains scientific material and a heart close to science. The lesson “Mixing Matter around” uses sand but us