构建化学观念是化学教学的核心与价值。化学教学具有三重表征:宏观(现象)表征、微观(结构)表征、符号表征。教师应帮助学生将宏观认识与微观认识有机统一、结合,建立起形成微粒观学习的有效规则、程序、产生式,从而建立起牢固的微粒观,发展学生的智慧技能,为学生的终身学习打下坚实的基础。在教学沪教版九年级化学“构成物质的基本微粒”一节的过程中,往往发现学生对于微观的认识能力比较弱,对于宏观与微观的认识不能有效地统一、 Constructing the concept of chemistry is the core and value of chemistry teaching. Chemistry teaching has triple representation: macroscopic (phenomenological) characterization, microscopic (structure) characterization, symbolic characterization. Teachers should help students to combine the macroscopical and microscopic knowledge organically and combine them to establish effective rules, procedures and productions that form the concept of microparticle study so as to establish a solid concept of microparticles and develop the students’ wisdom skills so as to lay down lifelong learning skills for students solid foundation. In the process of teaching “Nineth Grade Chemistry” of “Shanghai Medical Education Publishing House”, “Basic Particles that Make up Materials”, we often find that students have a relatively weak understanding of the micro-level and can not effectively unify their understanding of the macro- and micro-