1, understand the process of decimals, and understand and master the meaning of decimals.
2. Experience the process of decimal discovery and cognition, perceive the close relationship between knowledge and life and knowledge, and experience the learning methods of inquiry discovery and transfer reasoning.
3. Understand the generation process of mathematical knowledge, be educated by historical materialism, stimulate learning interest, and cultivate learning habits of hands-on practice and cooperative inquiry.
Teaching emphasis and difficulty: understanding and mastering the meaning of decimals.
Teaching courseware: multimedia courseware. Meter ruler.
Teaching process:
First reveal the topic: the meaning of decimals.
Second, the learning goal: 1, understand the generation process of decimals, and understand and master the meaning of decimals.
2. Experience the process of decimal discovery and cognition, perceive the close relationship between knowledge and life and knowledge, and experience the learning methods of inquiry discovery and transfer reasoning.
Three, self-study guidance (a): thinking preview before class:
Where do you see or use decimals? Give examples.
Under what circumstances are decimals produced?
Health: In view of the above two questions, talk about understanding and exchanging feelings.
Teacher: Show me the meter ruler and ask a classmate to measure the length of the blackboard. How many meters is rice?
Clear explanation: when measuring, you can't get an integer result, so you usually use decimals to express it.
So what does decimal mean?
Fourth, learn first.
1, self-study guide (2): Know a decimal place.
Read 50 pages by yourself and think:
Divide 1m into () parts, each part is () decimeter, expressed as () meter by fraction, or expressed as () meter by decimal.
How much are these three copies? How many meters is rice? How about seven servings like this?
2. Report after reflection.
3. Teacher: How did you get these decimals?
Five, after-school teaching:
Clear: divide 1 meter into 10 parts on average, which means that one or several parts are one tenth or several tenths, and the decimal is 0. 1 or 0.0.
Division; These decimals have only one decimal place after the decimal point, so we call such decimals decimal places. What do decimal places like this mean? (Make it clear that one decimal place represents a few tenths)
Six, know two decimal places, (the method is the same as above)
Seven, know three decimal places. (The method is the same as above)
Teacher: Divide the average 1m into 10, and know a decimal. How many parts can the average 1m be divided into to measure more accurately? (100 copies) So what new knowledge and discoveries will you have?
Students think, discuss, study and report their conclusions in groups.
I see. Divide 1 m into 100 parts, each part is 1 cm,1100 m, 0.0 1 m, and two parts are 2 cm, 2/100. If there are two decimal places after the decimal point, it is called two decimal places, and the two decimal places represent a few percent.
Divide 1 m into 1000 parts, each part is 1 mm,11000 m, 0.00 1 m, and two parts are 2 mm and 2/1m.
Eight. Extension:
Teacher: If we continue to divide 1m into 10000 shares and 100000 shares, that is to say, such 1 shares are 0.000 1m and 0.000 1m-
Nine, summarize the meaning of decimals:
Teacher: Looking back at the cognitive learning just now, what is the decimal? What does this mean?
Clear: Decimal means to divide 1 meter into 10, 100 and 1000. Numbers representing such one or more parts can be expressed in decimals, with one decimal place representing a few tenths, two decimal places representing a few percent and three decimal places representing a few thousandths.
Ten, classroom exercises, using feedback:
A) Tell the meaning of the following decimals:
0.3 yuan 0.45 m 0.089 kg
B) 7 cm = () decimeter = () meter 56 g = () kilogram
C) Two people share a piece of cake, and each person gets () piece?
Class summary: What knowledge have you gained?
Twelve. Assignment: ellipsis.
Thirteen, blackboard design:
The meaning of decimal
1 decimeter110m0.1meter, with one decimal place.
6 decimeters 6&; ......& gt& gt
Question 2: The meaning of decimals 3. Teaching design? Understanding decimal-decimal counting unit and numerical sequence table (lesson 2) Understanding decimal-decimal counting unit and numerical sequence table (lesson 2) Teaching content: Examples 3 and 4 of p.30~3 1 and corresponding attempts and exercises, and complete the sixth to 10 of Exercise 5. Teaching goal: 650. 2. In the process of feeling, experiencing and exploring ...? Common units of measurement-generation measurement, length unit and area unit-generation measurement, length unit and area unit. Teaching objectives 1. Make students understand the generation of measurement and deepen their understanding of the importance of measurement; Further master the commonly used units of length and area and the rate of advancement between units, so as to systematize the knowledge learned. The generation of commonly used units of measurement, the generation of commonly used units of measurement, length units and area units in teaching plans, and the teaching objectives of length units and area units in teaching plans are 1. Make students understand the generation of measurement and deepen their understanding of the importance of measurement; Further master the commonly used units of length and area and the rate of advancement between units, so as to systematize the knowledge learned. 2. Cultivate students' ability to query and collect information online and apply what they have learned .....? Teaching Design of Counting Unit, Numeric Order and Composition of Decimals Teaching Objective: Through practice, students can understand the meaning of decimals, master the counting unit, numerical order and composition of decimals, and be proficient in reading and writing decimals. The teaching goal of the teaching design of the understanding and counting unit of large numbers: knowledge and skills: 1, so that students can know that there are more than 10 thousand numbers in life; 2. Let students further understand the counting units such as ten thousand, one hundred thousand, one million, ten million and one hundred million, and know the series, digits, process and method of numbers. Let students experience the process of revealing the relationship between counting units, and master the commonly used units of measurement-generation measurement, length unit and area unit.
Question 3: Which master has the teaching record of the fourth grade of primary school mathematics in Qingdao Edition? Some classic records are also acceptable. Teaching content: standard experimental teaching materials for compulsory education courses? Mathematics "Qingdao Edition Five-year Grade Four Volume I"
Teaching objectives:
1. Understand the meaning of decimals through operation, observation, analogy and other activities, and learn to read and write decimals.
2. Experience the process of exploring the meaning of decimals, understand the relationship between decimals and life, and cultivate inductive ability.
3. In the process of learning the meaning of decimals, cultivate the interest in exploring knowledge, experience the fun of learning mathematics, and improve the ability of independent exploration and cooperation.
Teaching emphasis: understanding the meaning of decimals.
Teaching difficulties: go through the process of exploring the meaning of decimals and understand the counting unit of decimals.
Teaching preparation: multimedia courseware
Teaching process:
First, get the information and resources in the game.
Teacher: Now let's play a "happy answer" game. Please tell me quickly what kind of bird the teacher described. Are you ready?
Health: I'm ready.
Teacher: Please listen to the question: (1) is the most common poultry raised by human beings, weighing about 1. 1 kg.
(2) Its meat and eggs are often delicious on people's tables.
Health: Chicken.
Teacher: (Courseware) Estimate how many kilograms an egg has.
Health: 1 kg.
Teacher: A chicken 1. 1 kg.
Health: 0. 1 kg.
Teacher: Gao.
Health: 0.05 kg.
Teacher: It's very near. Look at the correct answer. Read it.
Health: 0.06 kg.
Teacher: Continue our quiz: It is the largest bird in the world at present, and its height can reach 2.75 meters.
Health: ostrich. (courseware)
Teacher: How much does an ostrich egg weigh?
Health: 2 kg.
Teacher: Gao.
Health: 1 kg.
Teacher: Low.
Health: 1.5 kg.
Teacher: Great. Let's see the correct answer. (Courseware: 1.65kg) Read it out quickly. Let's continue: it is a national protected animal, wearing white feathers and weighing 4.8 kilograms;
Health: Swan.
Teacher: Don't worry, keep listening to the question: * * * The scarlet head looks like Little Red Riding Hood.
Health: Red-crowned crane!
Teacher: Guess the quality of its eggs.
Health: 0. 1 kg.
Teacher: Low.
Health: 0.5 kg.
Teacher: Two are so heavy.
Health: 0.25 kg.
Teacher: Very impressive. (Courseware: 0.25 kg) Can you write this decimal? (blackboard writing: 0.25)
Teacher: It's a messenger of peace, weighing 0.45 Jin.
Health: Pigeons. (courseware)
Teacher: Estimate the weight of its eggs.
Health: 0.02 kg.
Teacher: That's really good. Almost close to the correct answer. (Courseware: 0.0 18kg). Who wants to write this time? (It says on the blackboard: 0.0 18) Everybody reach out and write with him.
Second, understand the meaning of decimals in operation
1. Understand the meaning of decimals.
Teacher: Through the quiz just now, the teacher found that students' extracurricular knowledge is really rich. How are they doing in math study? We will wait and see, and then enter our happy challenge session to see who will perform best in the next math activity. Are you confident to meet the challenge?
Health: Yes!
Teacher: Come on, look carefully. What numbers are used to represent the quality of these four kinds of eggs?
Student: Decimal system.
Teacher: We already know the decimal. Can you say more decimals? Who will come?
Health 1: 0.49
Health 2: 0.87
Health 3: 2.54 (health storytelling on the blackboard)
Teacher: How many decimal places are these?
Health: Two.
Teacher: Can you name several different decimals?
Health 1: 0.8
Health 2: 0.5
Teacher: Write them on the blackboard. (student blackboard writing)
Student: 0.875 (student blackboard writing)
Health: ...
Teacher: The teacher wants to write one, too, can he? (Teacher writes on the blackboard 0. 1)
Teacher: In this lesson, we will learn decimals with 0 before the decimal point. Then let's put this 2.54 in the question pocket. (Circle 2.54, arrow pointing to problem pocket)
Teacher: (referring to the decimals on the blackboard) Come and read together. (Original reading)
Teacher: It seems that everyone can read decimals and write decimals. What do these decimals mean Can you draw a picture to show it?
Health: Yes.
Teacher: Let's try. Let's start with the simplest decimal places. Which one do you want to draw?
Health 1: 0. 1
Health 2: 0.7
Health 3: ...
Teacher: Then draw a decimal that you like best. Students who have difficulties can choose the picture in the bag 1. (1 schoolbag has painting axes, rectangles, squares ... >>