估测或估计是《课程标准(2011年版)》突出强调的内容之一。估测是一种意识,具备这种意识,不仅有助于学生解决简单的实际生活问题,而且有助于培养学生用数学眼光观察和理解生活现象的习惯;估测也是一种能力,因为对事物进行估计时不仅需要对相关计量单位有很好的认识和把握,还要具有科学的估测方法和技巧,以确保估测结果的合理性。合理估计物体的轻重,对于三年级学 Estimation or estimation is one of the highlights of the Curriculum Standard (2011 Edition). Estimation is a kind of awareness. Having this kind of awareness can not only help students to solve the simple problem of actual life, but also help to cultivate the habit of students to observe and understand the phenomenon of life in a mathematical way. Estimation is also a capability because When things are estimated, not only need to have a good understanding of the relevant units of measurement and grasp, but also with scientific estimation methods and techniques to ensure the validity of the estimation results. Reasonable estimate of the severity of objects, for the third grade