The draft of "Tongfen" is 1, hello everyone!
Next, I will talk about how I chose the course Introduction.
First, the teaching content:
This lesson is the content of Unit 3 "Significance and Nature of Fractions" in Book 10 of Six-year Primary School Mathematics of Zhejiang Edition, P99 ~ 10 1.
Second, the positioning of teaching materials:
The total score is an application of the basic properties of fractions, which is to find the least common multiple of several numbers on the basis of students' mastery of the basic properties of fractions. At the same time, the total score is an important basis for the quartering operation, and it is an important step to compare the scores of different denominators and calculate the addition and subtraction of the scores of different denominators. So students must master it well. The textbook example 1 is the meaning and method of teaching general points, and the key point is to let students understand what this common denominator should be. Try the textbook to give three numbers a total score, including one point. The key is to remind students that when giving a total score, as long as the score is divided, the integer part remains unchanged. But after each band is divided into fractions, the integer part cannot be lost.
Third, the teaching objectives:
According to the teaching content of this course and the characteristics of students, I have determined the following teaching objectives:
1, so that students can know the meaning of the general points, understand and master the methods of the general points, and correctly understand the general points.
2. Cultivate students' thinking ability of observation, analysis and induction.
Four, the focus and difficulty of teaching materials:
In order to enable students to successfully achieve the teaching objectives, I have identified the following teaching priorities and difficulties.
Teaching emphasis: understand the meaning of general points and master the methods of general points.
Teaching difficulties: The key to understanding the arithmetic of total score and total score is to find the least common multiple of denominator as the common denominator.
Five, teaching methods:
In order to better highlight the key and difficult points of this lesson, I adopted the following teaching methods:
1, discussion method. Ask the students to summarize the meaning and methods of the general points through discussion.
2. Intuitive teaching with the help of projection demonstration is helpful for students to understand general calculus and cultivate their ability of observation and analysis.
3. Using different forms of exercises, students can consolidate what they have learned and get feedback in teaching.
4, persuasive, inspire and guide students, encourage students to speak actively, and guide students to use their mouths, brains and hands to gradually master new knowledge.
Sixth, learn the law:
Through the study of this lesson, students can learn to solve new problems with old knowledge. Through the observation and analysis of the operation demonstration, they summed up the significance and methods of general grading, which reflected the students' autonomy.
Seven, the teaching process:
First, review the bedding (show the small blackboard)
1. Find the least common multiple of the following numbers: 13 and 398 and 1 1 16 and 20.
2. (Textbook preparation questions) Divide the sum into scores with the initial letter 12 (fill in the blanks).
Design idea: The general score is based on finding the least common multiple of several numbers and the basic properties of the score. Therefore, I arranged a review to find the minimum common multiple of two numbers and the basic properties of fractions before the new lecture. The review question (1) reminds students how to find the least common multiple of two numbers when they are prime numbers, multiples and general relations. When reviewing question (2), let the students fill in the blanks first, and then talk about the basis of this filling in the blanks, so as to lay a good foundation for the general grading process. These two problems distract the difficulties in teaching.
Second, create scenarios and introduce new lessons.
Last class, we studied fractions. We know that the numerator and denominator of fractions can be changed without changing the size of fractions. So is there any other way to change the numerator and denominator of a fraction without changing the size? Today we are going to learn this new method.
Third, explore new knowledge.
1, for example 1.
Convert 1/6 and 2/9 into the same denominator scores equal to the original scores.
(1) into the same denominator score equal to the original, what should be determined first? (same denominator)
(2) How to determine this same denominator? We can simply call this denominator. Why? So what can we call the first step? (looking for common ground)
(3) How to divide 1/6 and 2/9 into fractions with the letter 18 but with the same size?
(4) Look at the picture and verify what has changed. What hasn't changed?
(Idea: When teaching the example 1, I first introduce the concept of fractions with different denominators through the fractions in the example, and then guide and inspire students to divide 1/6 and 2/9 into the same' fraction', and the denominator of public * * * must be a common multiple of 6 and 9, thus introducing the concept of common denominator, and then guiding students to think: For simple calculation, )
2. Summarize the meaning of general points and expose the topic.
You can know the name of the book we just made by reading a book.
3. Summarize the method of sharing points.
Through the calculation just now, we found that what is generally determined first in the general score? How to determine? So what?
4. Try to practice.
(1) Practice the textbook. Exercise 1 question.
(2) Try to divide 3/4, 2 and 7/8 equally.
Question (2) is another key point in teaching. First, lead the students to discuss what to do if there are three scores. Then discuss how to deal with scores, then students practice, teachers patrol, feedback and summarize the situation.
Design idea: In the process of teaching score, my focus is to solve the problem of how the original denominator and numerator are multiplied by the common denominator at the same time, and to guide students to think that the common denominator is several times that of the original denominator, and the denominator and numerator of the original score should be multiplied at the same time. )
Fourth, consolidate practice.
1, find the common denominator of the following two fractions in each group. (Emphasize the key to sharing key points)
2/3 and1/4,3/8 and 5/12,4/21and1/7,3/4 and 7/ 10.
1115 and 5/6, 7/ 12 and 5/8, 5/22 and 4/33, 10/39 and 9/52.
2. Separate the two scores of each group below. (Exercise the second question, emphasizing several special cases of general scores)
3. Separate the three scores of each group below. (Practice the third question.
Verb (abbreviation of verb) comprehensive exercise
1, Xiao Ming, Xiao Hong and Xiao Jun run the same long distance, with Xiao Ming taking 3/5 minutes, Xiao Hong taking 7/ 10 minutes and Xiao Jun taking 5/8 minutes. Please help them rank.
4. Find several simplest scores greater than 1/3 and less than 2/3.
Sixth, the class summary
1. What did you learn in this class? Let the students sum up by themselves, which will make the finishing point.
2. What is the score? What is the basis of the general score? How to divide it?
3. What are the similarities and differences between general points and approximate points?
My lecture is over, thank you leaders and teachers!
First of all, I would like to thank the three schools for giving me such a platform to show myself and a good learning opportunity. Let me tell you how I took this course.
First of all, talk about textbooks.
The teaching content of this lesson is the standard experimental textbook of nine-year compulsory education, Unit 4, Book 2, Grade 5 "General Score". General fraction is the application of the basic properties of fraction, which is to find the least common multiple of several numbers on the basis of mastering the basic properties of fraction. At the same time, the total score is an important basis for the quartering operation, and it is an important step to compare the scores of different denominators and calculate the addition and subtraction of the scores of different denominators. So students must master it well.
Second, talk about teaching objectives
According to the teaching content of this lesson, I have determined the following teaching objectives:
1, students know the meaning of total score, understand and master the method of total score, learn to divide two scores, and compare the scores of different denominators through the total score.
2. Cultivate students' thinking ability of observation, analysis and induction.
3. Experience success in discovery and feel the value of knowledge application in practice.
Third, talk about the key and difficult points of the textbook.
In order to enable students to achieve the teaching goal smoothly, I have determined the teaching emphasis and difficulty of this course.
Teaching emphasis: understand the meaning of general points and master the methods of general points.
Teaching difficulties: the key to understanding the arithmetic of the total score and the total score (find the least common multiple of the denominator as the common denominator. )
Fourth, the teaching method of speaking.
In order to better highlight the key and difficult points of this lesson, I adopted the following teaching methods:
1, discussion method. Ask the students to summarize the meaning and methods of the general points through discussion.
2. Teaching with the help of intuitive demonstration helps students to understand the reasoning of general points and cultivate their ability of observation and analysis.
3. Using oral answers, multimedia courseware and other forms of practice, students can consolidate their knowledge and get feedback in teaching.
4, persuasive, inspire and guide students, encourage students to speak actively, and guide students to use their mouths, brains and hands to gradually master new knowledge.
Verb (abbreviation of verb) and learning methods
Through the study of this lesson, students can learn to solve new problems with old knowledge. Through the observation and analysis of the operation demonstration, they summed up the significance and methods of general grading, which reflected the students' autonomy.
Six, the teaching process theory:
(1) Reproduction and Import
General fractions are learned on the basis of finding the least common multiple of several numbers and the basic properties of fractions. So before the new teaching, I used multimedia courseware to arrange the review of finding the least common multiple of two numbers, the basic properties of scores and comparing the sizes of scores. The review question (1) reminds students how to find the least common multiple of two numbers when they are prime numbers, multiples and general relations. Review question (2) Let the students review the comparison method of the scores of the same numerator and denominator, and let them try to fill in the blanks independently. Then ask the students to sum up the similarities between the two lines of scores, and how to compare the scores of the same denominator and the scores of the same numerator.
Lay a good foundation for the process of division. These two problems distract the difficulties in teaching.
(2) Guiding exploration
1. When teaching Example 4, I first asked the students to think: If the denominator and numerator of two fractions are different, how can they be compared? Students think and discuss in groups, and each group recommends a representative to express their ideas. At this time, there will be many different ideas: (1) decimal; With the help of line segment comparison; Comparison of chemical isomorphism scores; Comparison of fractions with the same denominator. First of all, I'm sure all these ideas are possible. Then, with the help of specific scores in the stem, the concept of scores with different denominators is introduced, and then students are guided to combine the same parent scores. The denominator of common denominator must be a common multiple of 5 and 4, which leads to the concept of common denominator, and then leads students to think about which common multiple should be taken as the common denominator for simple calculation, and then shows the key of common denominator.
3. In the teaching process of "Total Score", I mainly explained how to multiply the original denominator and numerator with the common denominator at the same time, and guided students to think that the common denominator is several times that of the original denominator, and the denominator and numerator of the original score should be multiplied at the same time. In order to help students really understand the general points, I borrowed multimedia presentations and achieved good results. On this basis, guide the students to summarize the significance and methods of the general evaluation by themselves against the blackboard writing.
4. After teaching example 4, guiding students to practice "doing one thing" is conducive to further consolidating the significance and methods of general points.
Lecture Notes of General Score 3 I. Talking about Teaching Materials
This lesson is the first lesson of Unit 4 "Significance and Nature of Fractions" in Grade Five of Primary School published by People's Education Press. Before that, students have learned the meaning, nature, common factor and common multiple of fractions. This lesson is the basis of learning the addition, subtraction and comparison of scores, and plays a connecting role.
Second, talk about learning.
The fifth-grade pupils still focus on concrete thinking, and abstract thinking is in a rapid development stage, but it is still low. Their abilities of observation, generalization and imagination have been developed to a certain extent. At the same time, students at this stage are active, easily distracted, and love to express their opinions, hoping to be recognized by teachers and classmates. In the process of teaching, I have grasped these characteristics. On the one hand, I pay attention to using intuitive teaching methods and introducing vivid life experiences, so as to stimulate students' interest in learning and seize their attention; On the other hand, create opportunities for students to express their opinions and give full play to their initiative.
Third, talk about teaching objectives.
According to the analysis of the teaching materials and the grasp of the learning situation, I set the following three-dimensional goals:
Knowledge and skills
Mastering the concept of total score can be used by comparing the sizes of different denominators.
Process and method
By comparing the processes with different denominator sizes, the analogical transfer ability is improved.
Emotional attitudes and values
By comparing the scores of different denominators, we can find the close relationship between mathematics and life, and improve our enthusiasm for learning and applying mathematics.
Fourth, talk about the key points and difficulties.
In the process of achieving the teaching objectives, I seized the main contradictions and key factors and set the following teaching difficulties:
focus
Master the total scores of different denominator scores.
difficulty
Master the total scores of different denominator scores.
Verb (abbreviation for verb) talks about teaching methods.
Modern teaching theory holds that students are the main body of learning and teachers are the organizers, guides and collaborators of learning activities. All teaching activities must be based on emphasizing students' initiative and enthusiasm. According to this idea, combined with the content characteristics of this class and the age characteristics of students, I adopt teaching methods such as teaching, inspiration and group discussion. Taking asking questions, analyzing problems and solving problems as the main line, the problem setting is always in the "nearest development zone" of students' knowledge, and students are encouraged to actively participate in teaching practice activities.
Sixth, talk about the teaching process.
The new curriculum standard points out that teaching is a process of interaction and development between teachers and students. In order to make the teaching process orderly and effective, I set the following teaching links for this class:
(A) the introduction of new courses
Introduce the situation and ask three questions to inspire students to think.
Question 1: There is a bucket of water divided into seven bottles. Xiong Da took two sips and Xiong Er took three sips. Who's drunk? Can you express this relationship with scores?
Question 2: The amount of mineral water per person in Xiong Er, Xiong Dahe is the same. The bear filled seven big bottles with his own water and drank three bottles. Xiong Er just filled 13 vial with his own water and drank three bottles. Who drinks more water? Can you express this inequality in fractions?
Question 3: The amount of a barrel of mineral water per person in Xiong Er, Xiong Dahe is the same. The bear filled seven big bottles with his own water and drank two of them. Xiong Er just filled 13 vial with his own water and drank 4 bottles. Can you tell who drinks too much?
The first two questions can be divided into the same denominator and the same numerator, and students can draw conclusions directly by using intuitive common sense. The third problem is that numerator and denominator are different, so it is difficult to judge. Let the students think about the reasons why they can't compare sizes, and then lead to a new lesson. The introduction of new curriculum is close to the reality of life. The problem is introduced step by step. Enlightening teaching methods are adopted to stimulate students' interest in learning, thus laying a good foundation for the smooth progress of this class.
(2) Explore new knowledge
In the inquiry session, according to the three questions in the lead-in session, I set up the following three inquiry activities.
Inquiry one, the inquiry of comparing size and denominator.
Teacher: Question 1: What is the reason for the size comparison?
Health: the bottles filled with water are the same size, that is, the units are the same.
Teacher: What is the reason why the corresponding scores can be compared?
Student: The unit of score is the same.
Teacher: So, what's the rule of comparing fractions with denominators?
Health: Compared with the denominator, if you look at molecules, there are more macromolecules and fewer micromolecules.
Teacher's blackboard writing
Inquiry 2: Compare the inquiry of the same molecular size.
Teacher: Question 2: What is the reason for comparing sizes?
Health: The number of bottles is the same, but the sizes are different.
Teacher: What is the reason why the corresponding scores can be compared?
Student: The molecules are the same, but the fractional units are different.
Teacher: Can we get the rules for comparing the same molecular scores from here?
Health: Compared with numerator, if you look at denominator, the number with large denominator will be smaller, and the number with small denominator will be larger.
Teacher's blackboard writing
Explore the third, compare the scores of different denominator.
Teacher: We learned the comparison of denominator size. So how do you compare the scores of different denominators? Let's ask each group leader to lead us to explore in groups. In the process of inquiry, we should pay attention to using the knowledge we have mastered about score comparison.
In the process of students' inquiry, teachers patrol and guide. There are two keys to this inquiry process: first, I want to compare scores with different denominators and the same denominator; Second, the theoretical basis for the equivalence of fractions with different denominators to fractions with the same denominator, that is, the nature of fractions. In the process of students' inquiry, teachers can give further hints according to the reality of students' inquiry. For example, it is difficult to compare the sizes of different denominators, so what kind of scores will we compare? What's the connection between them? Enlighten quietly.
After the inquiry, students share the inquiry results. The teacher clarified and emphasized the key points and wrote them on the blackboard. At this time, the concept of total score is given, and it is emphasized that the purpose of total score is to convert scores of different denominators into the same score unit.
Turn intuitive life problems into more abstract mathematical problems. Inspire students to describe practical problems in life with mathematical language, and explore new knowledge on this basis. It embodies the layered teaching concept from intuition to abstraction and from easy to difficult. The whole inquiry process highlights the division of roles between the teacher's organizer, the guide and the student's learning subject.
(3) Consolidate and improve
Activity 1
Carry out consolidation exercises in the form of group competitions. According to the rules of the game, the first correct group scored 3 points on the hero scoreboard of the month, and the second correct group scored 2 points on the hero scoreboard of the month; The third correct group's monthly hero standings 1 point. The other groups don't score. The title of the competition is as follows.
Compare scores.
(1)3/7 and 4/7
(2)8/ 19 and 8/2 1
(3)4/5 and 3/4
(4)3/8 and 5/6
(5)4/6 and 7/9
Activity 2
Ask each other questions at the same table. One plays the teacher's questions and the other plays the students' answers. If you get the right answer within the specified time, the teacher rubs his shoulders and beats his back. Instead, the students jostled each other and beat their chests.
In the process of consolidation and improvement, I pay attention to various forms of practice ideas, from easy to difficult, and disperse the consolidation of new knowledge in three activities. A variety of relatively new practice forms not only make students think, but also make students interact more physically and mentally. It embodies the teaching concept of primary school students playing at school and middle school playing.
(4) Summarize the homework
In the summary session, I use the following question-and-answer form to guide students to review and summarize the core content of this lesson. And set up after-school exercises 1 and 2 entitled after-school homework, so that students can share what they have learned with their parents through homework.
Seven, say blackboard writing design
Turn fractions into common denominators
Comparing scores with the same denominator, scores with larger numerator are larger.
Comparing the scores of the same molecule, the score with smaller denominator is larger.
Compare scores of different denominators, first turn them into scores of the same denominator, and then compare them.
2/7 = 26/914/13 = 28/91because 28/91> 26/9 1 so 4/ 13 & gt； 2/7
Changing a different denominator score into the same denominator score equal to the original score is called the total score.