初二上学期栽培植物一章里的马铃薯这一题材,根据中学生物教学大纲(草案)的规定,是在9月中旬以后才能进行讲授。但是到了9月中旬以后,有些地区马铃薯的茎叶已枯萎了,大部分马铃薯已收获了。而且马铃薯从栽到田地里到收获须经过五个多月的时间,我们却要用一两个课时就把它研究完。这就是摆在教学面前的问题。为了解决这些问题,为了使学生能够合乎认识规律的来掌握知识,按照教学 The topic of potatoes in the chapter on cultivated plants in the second semester of the second semester was not given until after mid-September according to the provisions of the Biology Curriculum (Draft) for Secondary Schools. But by the middle of September, the stems and leaves of potatoes in some areas have wilted, and most of the potatoes have been harvested. And it takes more than five months for the potatoes to reach the field and harvest, and we have to study it in one or two hours. This is the problem before teaching. In order to solve these problems, in order to enable students to conform to the law to grasp the knowledge, according to teaching