I. teaching material analysis
(A) the status and role of teaching materials
This lesson is the content of the third section of Chapter 10 "Preliminary Understanding of Statistics" in the seventh grade mathematics of China Normal University. It is a concept class to let students know the three basic statistics in data statistics, and it is also the basis for students to learn to analyze data and make decisions. The content of this lesson is closely related to students' life and can directly guide students' life practice.
(B) Teaching objectives and requirements
Knowledge goal: understand the meaning of average, mode and mode, master the calculation method of average, mode and mode, and make clear the fact that average and mode must exist and mode does not necessarily exist;
Ability goal: will calculate the average value of a set of data, will determine the mode and median of a relatively simple set of data, and cultivate the ability of independent thinking, innovation and teamwork;
Emotional goal: to experience the multifaceted nature of things and the necessity of learning to comprehensively analyze problems, infiltrate the moral concept of honesty and progress, and cultivate the spirit of hardship and innovation.
(C) the focus and difficulty of teaching
Teaching emphasis: the concepts of three basic statistics and their calculation and determination methods;
Teaching difficulties: the calculation of average and the determination of median mode.
Second, teaching methods and learning methods.
This course uses multimedia teaching platform; In concept teaching, with life examples as the background, the concepts of three statistics are abstracted from concrete facts, and the practice of calculating and determining the three statistics helps students understand and consolidate the concepts. In teaching activities, students are mainly inspired by questions, and students are attracted and motivated by vivid and interesting examples; In the whole process, the situational teaching method is adopted.
At the same time, it pays attention to cultivating students' reading comprehension ability and self-study cooperation ability. In the teaching process, students mainly learn through "inquiry self-study", "group discussion" and "mutual learning".
Third, the analysis of the teaching process
(1) Create a situation to stimulate interest (3 minutes)
The introduction adopts the "story method" introduction-from forty to ten. Through this lively and interesting story, students can fully experience the necessity of comprehensive understanding and analysis of data. How can we fully understand and analyze data? Today we will learn three statistics, which reflect a set of data from three different aspects-average, median and mode. It is also an effective way to focus students' attention through vivid stories.
(2) Self-study counseling to build new knowledge (1 1 min)
Put forward the concept: (3 minutes)
When the students are still immersed in interesting stories, ask the story: what level is the hero's performance? What is the average score? Which grade has the most people? The students answered one by one. On this basis, the teacher standardized the sentences in daily life (such as average grade) and abstracted the basic concepts in statistics (such as median).
This new concept can be based on students' existing life experience, which is easy to understand and remember.
Self-study instruction: (8 minutes)
Taking the study group as a unit and combining with the teaching materials, students must try to find out three statistics in the story and find out the calculation methods of average, median and mode. Group discussion and teacher's guidance.
Because the new textbook is more suitable for students to read, this section is closer to students' real life and students have more experiences, so it is not too difficult for students to understand. This can also give full play to students' subjectivity, cultivate students' self-study ability and teamwork ability, make full use of "student resources" to help each other and experience growth and development in the collective.
Integration: (20 minutes)
The concept of this lesson is dynamic and operable, which requires students to experience, understand and consolidate the concept in specific operation drills. To this end, first arrange the following exercise tasks for students, in which task 1 requires students to basically complete independently:
Work order:
1, fill in the form (6 minutes)
Data mean median model
15,20,20,22,35,38
3,0,- 1,5,9,-3, 14
-5,-4,-4,0,4,2 1
2. Discuss and modify in groups and summarize the solutions of three statistics. (4 minutes)
3, group communication, complete the exercises after the book. (4 minutes, 6 minutes)
At the same time, students will have some confusion when completing the task, such as: how to determine the pattern of the second row in the table? How to determine the median of the third line? What I hope the students can sum up may not be realized, but it can be experienced. When necessary, the teacher gives some guidance, such as visiting a place in the village head.
In this way, students can be familiar with the calculation methods of the three statistics in practice, especially in the "group exchange"; Deepen the understanding of concepts; Effectively consolidate concepts and algorithms.
(3) Explore exchanges and develop capabilities. (6 minutes)
As the content of this course, students' comprehensive ability can be appropriately strengthened, especially the comprehensive ability of reading pictures, analyzing data and calculating. To this end, I designed a motor problem:
Tom's math scores have two statistics:
Table 1
76 82 90 82 90 87 76 63 5 1 95
100 76 6 1 82 76 87 87 95 82 87
76 76 76 87 82 82 76 87 82 82
76 82 87 76 82 87 76 87 76 35
Table 2
Number of people:1112108351.
Grade 35 516163 76 82 87 90 95100.
We have calculated the average, median and mode of this class in the first table. Can these three statistics be calculated only from the data in the second table? Work in groups to see which group can calculate quickly and skillfully.
Using Table 2 to calculate, first of all, students need to understand the meaning of these data, and then correctly use the meaning of primary school multiplication to deduce the calculation method of "weighted average". Third, there are certain skills to determine the median of such data, which requires students to teach high thinking and analysis. This is a challenge to students, which is conducive to the improvement of students' "thinking method" and "will quality".
(4) After the new lesson, assign homework. (5 minutes)
Students exchange ideas.
The teacher added accordingly: the analysis of data must not be blind and one-sided, but should learn to analyze comprehensively; Determine the median: the key is to sort the data; Determine the mode: do frequency statistics.
Finish your homework 10.2. 1.
Students exchange ideas.
The teacher added accordingly: the analysis of data must not be blind and one-sided, but should learn to analyze comprehensively; Determine the median: the key is to sort the data; Determine the mode: do frequency statistics.