1, which is natural in reviewing and overstepping.
Before the new class, I designed such a review question: "I hope there are 50 students in the sixth grade of primary school." One person didn't come to school today because of illness. How many students have arrived at school in the sixth grade? " This not only reviewed the previous knowledge points, but also laid the foundation for the new knowledge to be learned below. Then, after the students successfully answer the review questions, they are required to convert the results into percentages, and directly tell the students "What is the percentage of the total number of students in the class, which is the attendance rate of the class today", and ask the students to write the formula of attendance rate against this sentence to understand why the formula should be multiplied by 100%. Then, the question of the review question is changed to
2. Students' real life is considered in the design and practice of examples.
When students learn to calculate the attendance rate in the example of the transformation of review questions, arrange students to calculate the attendance rate of our class today immediately. First, check students' understanding and mastery of attendance. Second, let students feel the mathematics around us. Third, the highest penetration attendance rate can reach 100%.
When designing the second example, I used the exam results of the previous unit as the material, and asked students to calculate the passing rate and high score rate of our class according to the number of people who got high scores through the exam, so that students could draw inferences about what is the passing rate and high score rate, further understand the meaning of percentage and feel the mathematical problems in our lives.
3. In the teaching process, pay attention to all students and take students as the main body for teaching.
Ask the students to explain the meaning of the required percentage and tell the calculation formula every time they give a question, so as to pave the way for students to understand and master new knowledge. After that, let the students discuss the relationship between attendance, pass rate, high score, germination rate and 1, and further understand the meaning of percentage.
This lesson also has many shortcomings:
1, the second condition of the review question can actually be designed more simply. Just say "49 people came today", so that students can understand it more easily and spend less time on calculation. Then, at the end of the new class, use a turning question as thinking training, which may better enable students to think and answer on the basis of understanding what they have learned in this class.
2. When consolidating the practice, because the * * * has already rung after class, this process is carried out in a hurry, which leads to the students' mistakes not being discovered in time (only after class), so we must pay attention to it in the future.
Teaching content Example 2 on page 85 of the textbook, follow suit and practice the corresponding exercises in 18.
Teaching objectives
Knowledge and skills:
Let students further understand and master the quantitative relationship in the percentage application problem, and learn to solve the percentage problem of "what is the percentage of a number";
Process and method:
Further cultivate students' ability to apply what they have learned to solve problems, the ability to explore knowledge independently and the habit of cooperation and communication;
Emotions, attitudes and values:
Enable students to further understand the relationship between knowledge and cultivate health awareness.
The key and difficult points in teaching will solve the application problem of finding the percentage of a number.
Teaching preparation courseware
teaching process
First, review old knowledge and introduce new lessons.
1. Teacher: Students, please recall what we learned last class. How to solve it? In this lesson, we will continue to learn to solve problems with percentages.
2. oral calculation.
3. Oral answer:
(1) How much is 30 meters 45?
(2) What is 9 100 of 400?
4. Change "than" to "yes".
5. Example 2: A survey in Chunlei Primary School showed that students suffering from dental diseases accounted for 15 of the whole school. There are 750 students in Chunlei Primary School. How many students have dental diseases?
Students answer independently.
The teacher concluded: We already know that percentage is actually a special grade. Today, we are going to learn to solve the problem "What is the percentage of a number".
Write on the blackboard.
Second, explore independently and gain new knowledge.
1. Example 2: A survey in Chunlei Primary School showed that students suffering from dental diseases accounted for 20% of the whole school. There are 750 students in Chunlei Primary School. How many students have dental diseases?
(1) Students' group discussion algorithm.
(2) student reports.
(3) Summary: Finding the percentage of a number is the same as finding the score of a number.
(4) Students can solve problems independently.
(5) courseware modification:
Method 1:
750×20%
=750×
=750×0.2
= 150 (person)
A: Dental students 150 people.
Method 2:
750×20%
=750×
=750×
= 150 (person)
A: Dental students 150 people.
Tell me how to find the percentage of a number.
Third, consolidate the practice.
1. Comparison exercise:
(1) There are 45 students in Class One, Grade Five, and the score of 15 in last semester's math exam is above 80. How many students have more than 80 points?
(2) There are 45 students in Class One, Grade Five, and 20% of them scored 80 points or more in the math exam last semester. How many students have more than 80 points?
(3) Of the 480 students in Baihua Hutong Primary School, only 5% did not participate in accident insurance. How many students didn't participate in accident insurance?
(4) Of the 480 students in Baihua Hutong Primary School, only 5% did not participate in accident insurance. How many students have participated in accident insurance?
(5) 2,400 eggs were hatched in the chicken farm, and 5% were not hatched. How many chickens haven't hatched?
(6) 2,400 eggs were hatched in the chicken farm, and 5% were not hatched. How many chicks have hatched?
2. Strengthen practice.
(1)7. There are 45 students in Class One, Grade Six, including the final long jump test last semester.
80% of the students passed. How many students passed?
(2) The number of boys in Chengguan No.1 Middle School and Chengguan No.2 Middle School respectively accounts for the total number of students in the whole school.
52% and 54%, 800 in Chengguan No.1 Middle School and 750 in Chengguan No.2 Middle School.
Man, which school has more boys? How many people are there?
Courseware modifies the answer.
Fourth, summarize this lesson.
What did you learn in this class?
blackboard-writing design
What is the percentage of a number?
Example 2: A survey in Chunlei Primary School shows that students suffering from dental diseases account for 15 of the whole school. There are 750 students in Chunlei Primary School. How many students have dental diseases?
Method 1:
750×20%
=750×
=750×0.2
= 150 (person)
A: Dental students 150 people.
Method 2:
750×20%
=750×
=750×
= 150 (person)
A: Dental students 150 people.
It is a simple application of percentage to examine the PPT courseware for calculating the percentage of a number published by Xinmin Education Press. This part of the content is taught on the basis that students understand the meaning of percentage, master the mutual method of percentage, decimal and fraction, and can "calculate the score of one number to another". Through teaching, students can further understand the percentage.
There are two examples in the textbook for teaching. Example 4 is a common problem in teaching. First, the distance between Wang Hong and other three people is represented by a histogram, so that students can not only know how many kilometers each person runs, but also recall old knowledge and intuitively feel the numbers related to scores in the picture, providing experience for solving the problem that "one number is a few percent of another number"; Then guide students to link the question "How far Li Fang runs is Wang Hong's" and "How far Li Fang runs is Wang Hong's", so that students can transfer their existing problem-solving experience to new problem situations; Finally, the textbook guides the calculation skills of finding percentage. Write the quotient in decimal form first, and then rewrite the decimal into percentage, so that students can understand the simplicity of expressing the result of division with decimal. Example 5 Practical problems of finding percentage in teaching. The textbook first helps students understand that "attendance is the percentage of actual attendance to the number of people who should attend", and explains that seeking percentage is the percentage of one number to another. After calculating the attendance of the track and field team on Monday, let the students choose the data of two days to calculate the attendance, and consolidate their understanding of the attendance. On this basis, the textbook allows students to ask questions about the survival rate of saplings and tell examples of percentage in life, so that students can further understand the meaning of percentage and feel the wide application of percentage in life and production.
The teaching focus of this lesson is to understand and master the idea and method of "what percentage of one number is another number". The difficulty is to analyze the quantitative relationship and find the correct unit "1".
[Teaching objectives]
1. Through the transfer of knowledge, let students understand the idea of solving the application problem "What percentage is a number" and master the calculation method of percentage.
2. In the process of solving practical problems, we can further understand the internal relationship between mathematical knowledge, thus being inspired by the dialectical materialism view that there is a universal relationship between things.
3. Understand the application of percentage in specific life problems, stimulate students' enthusiasm for learning, and further establish confidence in learning mathematics well.
[Teaching process]
First, pave the way for pregnancy
1. What is a percentage?
2. Rewrite the following figures into percentages.
0.6 7/ 10 3.5 5/8 1
3. Give the statistical chart of Example 4, and observe carefully to get information.
(1) Compare the multiple relation of any two quantities, and put forward the question "A fraction of one number is a fraction of another number". How should I ask this question?
How far does Li Fang run than Wang Hong?
How far does Wang Hong run than Lin Xiaogang?
……
(2) Free oral answers and timely questions: Who is better than who? Who is this unit "1"?
(3) Summary: How to find the score of one number to another?
4. These questions all express the multiple relationship between two people's running distance and scores. Percentages also represent multiples. Can you change "what percentage of a number is another number" to "what percentage of a number is another number"?
In this lesson, we will learn to solve a simple practical problem: what percentage is one number in another?
[Comment: According to the law of knowledge transfer, we should review the meaning of percentage at the beginning of class, and the method of converting fractions and decimals into percentages, focusing on the problem-solving method of "the fraction of one number is a fraction of another number", paving the way for the smooth exploration of new knowledge and the transition to new courses. ]
2. Explore new knowledge
(1) Teaching Example 4: Find what percentage of one number is another.
1. Change the review question "What percentage of the distance Li Fang runs is Wang Hong" to "What percentage of the distance Li Fang runs is Wang Hong"?
2. Try to answer and find the question:
Dialogue: Do you want to try to find out for yourself?
The students try to do it and say their names.
Dialogue: What problems did the students meet that need to be discussed?
3. Students communicate freely, and teachers guide their thinking in a timely manner:
(1) Discuss how to formulate
Thinking: Why? what do you think?
Introduction: Which two quantities are being compared and which quantity is regarded as the unit "1"? What percentage of the distance Li Fang runs is that of Wang Hong?
Summary: This question takes the distance run by Wang Hong as the unit "1", and the distance run by Li Fang is a few percent of that of Wang Hong. In fact, it's like asking Li Fang to run a few percent of Wang Hong to solve the problem.
Teaching content: The sixth grade compulsory education course of People's Education Press, Volume I, 93 pages, Example 3.
Teaching objectives:
1, master a slightly more complicated solution with more than one number;
2. Further understand the relationship between the percentage application problem and the corresponding score application problem;
3. Enhance the awareness of application and realize the application of percentage in real life;
4. Improve students' ability of analogy, analysis and problem solving.
Teaching emphases and difficulties:
Find the unit "1" and master the solution to the problem of how many numbers are more than numbers.
First, review the old knowledge, review the groundwork
( 1), 3/4× 42/3 ÷ 2/3 1+ 12%
(2) What is 3/5 of 20? How much is 70% of 30?
(Design intention: Review the calculation method of "What is the fraction (percentage) of a number" and the related calculation of percentage, so as to pave the way for new knowledge. )
Second, teacher-student interaction, exploring new knowledge
(1) Ask questions independently and generate questions.
1. Teacher's oral information: the school library has 1400 books, which has increased by 12% this year.
2. Retell the information you just heard.
(Design intention: cultivate students' memory ability and good habit of listening to lectures. )
3. Students ask relevant percentage questions and introduce examples.
Default question: ① How many volumes have been added? 2. How many books are there this year? (3) What percentage of books are there this year?
(Design intention: Brainstorming questions put students in the main position of learning, which not only cultivated students' problem consciousness, but also fully mobilized students' attention to the classroom, paving the way for later teaching. )
(2) solving problems, giving examples.
1, example 3:
Teacher's statement: Add the information just now and the second question raised by the students, that is, Example 3 we are going to learn today.
Example 3: The collection of books in the school library is 1400 volumes, which has increased by 12% this year. How many books are there now?
2. Analyze the quantitative relationship and determine the method to solve the problem.
(1), focusing on guiding and analyzing "the number of books increased this year 12%".
Guidance: What does the increase in the number of books and albums 12% mean this year? Have you seen similar problems there? Would you solve it if you changed 12% into the number of components? We can solve the problem of percentage application by solving the problem of score application. What is the equivalence relation? (Number of books this year = number of original books+number of books added) What is the unit "1"? What shall we ask first? (that is, the question 1) What do you need to increase the number of books? How to go public? (1400× 12%) The teacher taught a calculation method of multiplying a number by a percentage. )
(Design intention: Review the old knowledge, introduce the new with the old, and let the students literally understand the meaning of "the number of books increased this year 12%" with the help of the ideas and methods of solving fractional application problems, pay attention to the transfer and analogy of knowledge, learn the problem-solving methods, give students a space to explore and experience the formation process of knowledge. )
(2) According to the equivalence relation expression, the integrity of the process is emphasized.
(Design intention: According to students' reality, let students learn some calculation methods and skills, and cultivate students' good thinking habits and study habits. )
(3) Draw students to talk about the meaning of the formula, review the thinking of solving problems and talk about the main points of solving problems. (Find the unit "1" and its equivalent relationship. )
(Design intention: Let students learn the ideas and methods of solving problems by reviewing the ideas of solving problems. )
What is the percentage of a number in the first volume of the fifth grade mathematics teaching plan published by People's Education Press? Hello, I'm glad to answer your questions:
Percentage refers to:
When a number is multiplied by two digits, the decimal is the percentage of the number.
I wish you a happy life and progress in your study!
If you have any questions about this answer, please ask.
Remember to adopt when you are satisfied, thank you ~ ~ ~
Xinmin education publishing house, the first volume of mathematics in the sixth grade of primary school, what is the percentage of a number? Reflection on teaching design and teaching content: the first volume of compulsory education curriculum for grade six, People's Education Press, 93 pages, Example 3.
Teaching objectives:
1, master a slightly more complicated solution with more than one number;
2. Further understand the relationship between the percentage application problem and the corresponding score application problem;
3. Enhance the awareness of application and realize the application of percentage in real life;
4. Improve students' ability of analogy, analysis and problem solving.
Teaching emphases and difficulties:
Find the unit "1" and master the solution to the problem of how many numbers are more than numbers.
Teaching process:
First, review the old knowledge, review the groundwork
( 1), 3/4× 42/3 ÷ 2/3 1+ 12%
(2) What is 3/5 of 20? How much is 70% of 30?
(Design intention: Review the calculation method of "What is the fraction (percentage) of a number" and the related calculation of percentage, so as to pave the way for new knowledge. )
Second, teacher-student interaction, exploring new knowledge
(1) Ask questions independently and generate questions.
1. Teacher's oral information: the school library has 1400 books, which has increased by 12% this year.
2. Retell the information you just heard.
(Design intention: cultivate students' memory ability and good habit of listening to lectures. )
3. Students ask relevant percentage questions and introduce examples.
Default question: ① How many volumes have been added? 2. How many books are there this year? (3) What percentage of books are there this year?
(Design intention: Brainstorming questions put students in the main position of learning, which not only cultivated students' problem consciousness, but also fully mobilized students' attention to the classroom, paving the way for later teaching. )
(2) solving problems, giving examples.
1, example 3:
Teacher's statement: Add the information just now and the second question raised by the students, that is, Example 3 we are going to learn today.
Example 3: The collection of books in the school library is 1400 volumes, which has increased by 12% this year. How many books are there now?
2. Analyze the quantitative relationship and determine the method to solve the problem.
(1), focusing on guiding and analyzing "the number of books increased this year 12%".
Guidance: What does the increase in the number of books and albums 12% mean this year? Have you seen similar problems there? Would you solve it if you changed 12% into the number of components? We can solve the problem of percentage application by solving the problem of score application. What is the equivalence relation? (Number of books this year = number of original books+number of books added) What is the unit "1"? What shall we ask first? (that is, the question 1) What do you need to increase the number of books? How to go public? (1400× 12%) The teacher taught a calculation method of multiplying a number by a percentage. )
(Design intention: Review the old knowledge, introduce the new with the old, and let the students literally understand the meaning of "the number of books increased this year 12%" with the help of the ideas and methods of solving fractional application problems, pay attention to the transfer and analogy of knowledge, learn the problem-solving methods, give students a space to explore and experience the formation process of knowledge. )
(2) According to the equivalence relation expression, the integrity of the process is emphasized.
(Design intention: According to students' reality, let students learn some calculation methods and skills, and cultivate students' good thinking habits and study habits. )
(3) Draw students to talk about the meaning of the formula, review the thinking of solving problems and talk about the main points of solving problems. (Find the unit "1" and its equivalent relationship. )
(Design intention: Let students learn the ideas and methods of solving problems by reviewing the ideas of solving problems. )
(3), a problem with multiple solutions, expand thinking.
Thinking: Is there any other solution to this kind of problem?
(1), hint: Think with the help of the questions just raised.
(2) Students think independently. 1400× ( 1+ 12%)
(3) the idea of "pumping students".
(4) Analyze "What percentage of books are there this year?"
Design intention: Infiltrate the idea of combining numbers and shapes, and let students learn to solve problems at the same time.
(5) Identify the key points to solve the problem.
(6), solution column.
(4) Analyze the features and classify them independently.
1, teachers and students are divided together, which belongs to the question "What is more (less) than a number?" .
2. Review the ideas and methods to solve such problems.
(Design intention: to cultivate students' ability of analysis, classification and autonomous learning. )
Third, combine with reality and improve through comparison.
1, adaptation example 3 and the answer.
There are 1568 books in the school library, and the number of books has increased by 12% this year. How many books are there this year?
(1), students think independently and answer independently.
(2) Answer in groups.
(3) communicate with the whole class.
2. Analyze the similarities and differences between this problem and the example.
3. Compare the similarities and differences between this kind of questions learned today and the fractional application questions.
(Design intention: To make students more proficient in problem-solving methods, that is, no matter how the conditions change, they must first understand the quantitative relationship and identify the unit "1", so as to further improve students' analytical ability, summing-up ability and thinking level. )
Fourth, contact life and deepen new knowledge.
1, over 30 meters, 60% is () meters. 40 kg is 20% less than ().
2. Do 1 questions.
A canteen bought 1000 Jin of cabbage this winter, and has eaten 60%. How many kilograms are left?
(Design intention: Practice embodies the hierarchy, so that students can have a high-level training process in their thinking and improve their comprehensive application ability. )
Five, the class summary:
What did you gain from this class?
(Design intention: Students review and reflect on the knowledge and methods they have learned, sum up experience and learn from each other's strengths. )
Sixth, assign homework.
Write down today's harvest in your diary.
Design intention: By keeping a diary, we can have a process of reviewing and sorting out the gains in class, which is helpful to systematize knowledge and organize methods, which not only consolidates what we have learned, but also cultivates students' logical thinking ability and language expression ability.
Solve problems with percentages.
Find an application problem that is a few percent more or a few percent less than the number
Method 1: Method 2:
Current book quantity = original book quantity+increased book quantity = original book quantity × (1+ 12%)
1400× 12% 1400×( 1+ 12%)
= 168 (volume) =1400×112%
1400+168 = 1568 (volume) =1568 (volume)
A: There are 1568 books. A: There are 1568 books.
Teaching reflection: The design of this course is mainly to pave the way for students to solve an application problem that is more or less than the score in the fractional application problem, so as to promote the transfer of students' knowledge, and let students use their existing knowledge and experience to explore the methods of solving problems independently, so as to better master the ideas and methods of solving an application problem that is more or less than the score, and then find out their similarities and differences through the comparison of solving ideas. The whole teaching process is very smooth, but the disadvantage is that the key points of blackboard writing are not written in red pen, which leaves a poor impression on students. Students are slow in calculating the percentage of large numbers, and their methods and skills are not properly selected, which needs to be strengthened.
The first volume of mathematics in grade six is to find out what the percentage of a number is. Teaching material analysis, Hebei Education Edition.
The teaching content of this section is to solve practical problems according to the meaning and calculation of fractional multiplication. There are two types of fractional multiplication problem solving: one is that the data contains fractions, but the quantitative relationship and solving method are the same as integers, such as questions 2, 9, 7 and 9 in Exercise 3, which belong to this category. The other is the problem of finding the fraction of a number.
(2) Analysis of learning situation
Through the previous study, students have understood the significance and calculation method of fractional multiplication. Finding the quantitative relationship of a number's fraction is special, and the line graph can clearly express the relationship between the quantities. Therefore, in teaching, students can analyze the quantitative relationship through line graphs and choose the best algorithm from many algorithms to solve practical problems.
(3) Target positioning
According to the students' life experience and knowledge background and the knowledge characteristics of this course, I set the following teaching objectives:
1, master the simple ideas and methods to solve the application problems of fractional multiplication;
2. Learn how to observe and draw a line graph to help analyze the quantitative relationship.
3, in the process of learning, cultivate the ability to analyze and solve problems.
Key points: let students learn to solve problems with the knowledge of fractional multiplication, which reflects the diversity of problem-solving strategies.
Difficulties: Accurately judge which quantity is which fraction, that is, who is the unit "1".
20 15 what is the percentage of a number in unit 6 of the first volume of sixth grade mathematics?
1. Understand and master the quantitative relationship of "What is the percentage of a number" and correctly answer the practical question of "What is the percentage of a number".
2. Correctly analyze the quantitative relationship in the topic and improve the ability to solve practical problems.
3. Let students feel the close connection between mathematics and life, and apply what they have learned.
Second, teaching focus: understand and master the quantitative relationship of "what is the percentage of a number".
Third, teaching difficulties: correctly analyze and answer "What is the percentage of a number?"
Fourth, prepare teaching AIDS: multimedia courseware.
Verb (abbreviation of verb) teaching process;
First, the scene introduction:
1, classmates, do you know any interesting places in Weihai? The students exchanged views on the tourist attractions in Weihai.
2. Show the scenic spots of Weihai on the big screen.
Second, the new curriculum teaching:
1. Information on the development of tourism in Weihai:
During the Golden Week last year, there were 1 10,000 tourists visiting Weihai, 40% of whom came to Liu Gongdao.
2. Let the students exchange the information in the topic, and guide the students to understand the meaning of 40%: it means that the tourists coming to Liu Gongdao account for 40% of the tourists coming to Weihai.
Step 3 ask questions:
Can you ask math questions based on the above information?
Q: How many thousands of tourists visit Liu Gongdao?
4. Find a classmate to play with and communicate with the whole class.
Step 5 practice:
(1) An article is 9600 words. Xiao Ming typed 40% of the full text. How many words did Xiao Ming type?
(2) To build a 300-meter-long road, the first stage will be completed by 30%. How many meters was built in the first phase?
Third, accumulation and expansion:
Last year, Weihai's tourism revenue was about/kloc-0.2 billion yuan, a year-on-year increase of 20%. What is the tourism income of Weihai this year?
1, let students understand the meaning of 20%.
2. Guide students to understand that Weihai's tourism income this year is last year's income.
What is the percentage?
3. During the Golden Week last year, there were 1 10,000 tourists visiting Weihai, 40% of whom came to Liu Gongdao. How many tourists are there in Liu Gongdao?
4. Last year, Weihai's tourism revenue was about1200 million yuan, up 20% year-on-year. How much is Weihai's tourism revenue this year?
Riddles are designed according to human cognitive characteristics, and people often need to solve them through metaphor and association. The following is what