教材背景简述:本单元是三年级《可能性》单元的延伸。在三年级,学生已初步体验了生活中确定和不确定现象,并会用“一定”“不可能”和“可能”正确地描述这些现象。能列举出简单的不确定事件可能出现的所有结果,知道其不同结果出现的可能性是有大小的,并领悟到可能性大小与其可能出现的不同结果所 Brief Description of the Teaching Material: This module is an extension of the “Possibility” module in the third grade. In the third grade, students have initially experienced determinations and uncertainties in life and will correctly describe these phenomena with “must ” “impossible ” and “may ”. Can list all the possible outcomes of a simple uncertain event, knowing that different outcomes are likely to be of the same size and perceive the likelihood of different outcomes as they may appear