在六年级上《保持水土》,要学生分组做植被对保持水土的作用实验时,先让学生讨论了为什么要使一块木板上的草皮与另一块木板上的土层同样大,同样厚,为什么两块木板斜放的坡度要相同,又为什么用喷壶往木板上浇水要同样高度,放同样多的水。当学生搞清这是一种对比实验,只有其它条件都相同时,才能保证所要检测条件的可比性之后,有一个学生提出,用喷壶浇水,即使在同样高度,浇同 In the sixth grade, “Maintaining soil and water” and requiring students to do vegetation to maintain the role of soil and water In the experiment, students were asked to discuss why the turf on one plank was the same size and thickness as the plank on another plank. Why Diagonal slope of the two pieces of wood to be the same, why watering the watering cans to the same height, put the same amount of water. When the students figure out that this is a comparative experiment, only when other conditions are the same, to ensure the comparability of the conditions to be tested, one student suggested that watering with a watering can, even at the same height,