“鸡兔同笼”是人教版小学数学六年级上册“数学广角”中的内容。执教这一课时,在“探究算法”环节中,让学生猜猜笼子中可能有鸡兔各几只时,出现了冷场。这一环节,在设计时我认为对六年级学生来说是很简单的。可在实际教学中,并非如此。这到底是为什么呢?在课后与学生交流时发现他们觉得这似乎无从猜起,随意猜的都是错的,所以造成了冷场。原来“猜”也不是如此简单!试想,当我们第一次接触“鸡兔同笼”问题时,你会怎么办?大多数人可能都会不断地猜(配),最终找到解决问题的方法。“猜”是一件大家都会去做的事情,是一件多么质朴的事情。正如波利亚所说:“在数学领域中,猜想是合理的、值得尊重的,是负责任的态度。”那么如何让学生“敢猜”“会猜”呢?针对这一问题,我对“探究算法”环节进行了重新设计。这是 “Chicken rabbit with cage ” is the PEP sixth grade on the book “Mathematics wide angle ” in the content. When coaching this class, there was a cold field in “Explore Algorithms” where students guessed that there might be a few chickens in their cage. This aspect, at design time, I think it is very simple for sixth graders. Can be in the actual teaching, not so. This is why in the end? After the class and students to communicate that they find it seems impossible to guess, guessing are wrong, resulting in a cold market. The original “guess” is not so simple! Imagine, when we first contact with “chicken with rabbit cage” problem, what would you do? Most people may continue to guess (with), and finally find a solution The problem’s method. It’s a rustic thing that “guess” is something that everybody can do. As Polia said: “In the field of mathematics, the conjecture is reasonable and worthy of respect, and it is a responsible attitude.” So how do students get “dare to guess” and “guess”? This issue, I “exploration algorithm ” link has been redesigned. this is