小学生习惯于单向思维,按照固有的认识框架,定向推演,结果费尽了力气,却走向了死胡同。在这种情况下,教师如果能帮助学生摆脱固有的思维定势,倒过来思索一番,倒可能使学生豁然开朗。在《詹天佑》一课中,詹天佑想加快工程进度,计划从山两端同时开凿隧道,又担心隧道的方向错位,那 Primary school students accustomed to one-way thinking, according to the inherent understanding of the framework, directed deduction, the result of effort, but to a dead end. In this case, if teachers can help students get rid of the inherent thinking and thinking about it, it may make students suddenly see it. In “Zhan Tianyou” class, Zhan Tianyou wanted to speed up the progress of the project, plans to tunnel both ends of the mountain at the same time, but also worried that the direction of the tunnel misplaced, that