一、准备阶段课前让学生以小组为单位,根据本节课的教学目标,写出实验计划,确定实验器材,设计实验环节。然后再进行全班集体讨论,集思广益,选出最佳的设计方案。方案确定下来后,进行小组任务分配,教师检查和指导。二、实施阶段1.实验器材塑料托盘(40cm×60cm)若干;泡沫箱若干;草皮、黄土、粘土;筛眼大小不同的洒水壶若干把。2.实验过程课前下发实验记录单,课上学生分组进行实验。(1)铺满草皮、铺一半草皮、铺满黄土的塑料托盘3 First, the preparatory phase for students to group as a unit, according to the teaching objectives of this lesson, write out the experimental plan to determine the experimental equipment, design and experiment. And then the class collective discussion, brainstorming, choose the best design. After the program is finalized, the group task assignment, teacher inspection and guidance. Second, the implementation phase 1. Experimental equipment Plastic tray (40cm × 60cm) number; a number of foam boxes; turf, loess, clay; sieve size of a number of different sprinkler. 2 experimental process before the test record issued a single class, class students to experiment. (1) covered with turf, paved half turf, covered with loess plastic tray 3