Mathematics teaching design for the second grade of primary school
Teaching content: understanding grams and kilograms. (textbook page 100- 104)
Teaching objectives:
1, in specific life situations, let students feel and know the unit of mass grams and kilograms, and initially establish the concepts of 1g and 1kg, knowing 1kg = 1000g.
2. Let students know how to weigh objects with scales.
3. On the basis of establishing the concept of quality, let students form the consciousness of measuring the quality of objects.
Key points and difficulties:
Key points: Establish the concepts of grams and kilograms and know their relationship.
Difficulties: the establishment of the concepts of grams and kilograms.
Teaching AIDS:
Courseware, 2-cent coins, soybeans, scales, two bags of 500 grams of salt, platform scales, small items brought by oneself, etc.
Teaching process:
First, the problem situation:
Teacher: Students, do you want to know what math knowledge you found in the supermarket today? Take a closer look. (Courseware display: textbook 100 page scene map)
Health 1: Everyone is discussing quality-related topics.
Health 2: From the picture, we know that five apples weigh 1kg, a pot of soybean oil weighs 5kg, and a packet of biscuits weighs 1 10g. ...
Teacher: The quality of objects is often used in our daily life. In the past, the mass units commonly used in China were "Jin" and "Liang", and now the mass units commonly used in the world are "gram" and "kilogram", which is also a problem we will study together today.
Design intention: From common life scenes, guide students to find that the quality of objects is closely related to life.
Second, independent inquiry:
1, teaching example 1.
Teacher: Watch carefully and tell me what you find. (Courseware demonstration: textbook page 65438 +00 1, example 1)
Health 1: I know that a box of chewing gum weighs 3 grams, a bag of chrysanthemum tea weighs 12 grams, and a bag of delicious melon seeds weighs 100 grams.
Health 2: I found that these lighter items are all in grams.
Teacher: Yes, we usually use grams as the unit for measuring lighter items. "gram" is an international unit of mass, which is represented by the letter "g"
Teacher: So what are commonly used to weigh lighter items? The teacher told everyone that there is a weighing tool called a balance, and lighter items are often called scales. Now, students, please weigh what weighs 1 g around you with scales in the group.
Students measure the weight of lighter items in the group, looking for items with the weight of 1 g, and the teacher visits to understand the situation.
Organize students to communicate and talk about the results of group measurement.
(1 2 cent coin weighs about 1 g)
Teacher: Which of the following items is estimated to be lighter than 1g? (Courseware demonstration: "Do it" on page 10 1 in the textbook)
Assign students to answer and give their opinions in time.
Teacher: What other things in life are lighter than 1g?
Raw 1: a small piece of rubber is lighter than 1 g.
Health 2: A hair is lighter than1g. ……
2. Teaching example 2.
Teacher: Actually, in our life, there are more items whose mass exceeds 1g or even heavier. So what do we usually use as the unit of heavier items? Everyone will know at a glance. (Courseware demonstration: Example 2 on page 102 is shown above)
Health 1: A bucket of laundry detergent weighs 5 kilograms, so I think it should be used to weigh the kilograms.
Health 2: A box of apples is 25 kilograms. I also think it is a relatively heavy item measured by "kilograms".
Teacher: "kilogram" is also an international unit of mass, which is represented by the letter "kg".
Teacher: Look carefully. The box of apples says "net content". What is "net content"?
Health: "net content" refers to the quality of this box of apples, not including the quality of the box.
Teacher: Yes, the word "net content" is often used in life. It refers to the actual quality of the items in the barrels and boxes.
Think about it. How much does1000g weigh? For example.
Health: One pack of salt commonly used in life weighs 500 grams, and the mass of two packs of salt is 1000 grams.
Teacher: What do you think is the relationship between "kilogram" and "gram"?
Health: 1kg = 1000g.
Teacher: Who knows which scales in life use "kilograms" as the unit?
Health 1: I have seen electronic scales and bench scales in supermarkets and food stalls.
Health 2: I met weighing scale to weigh her during the physical examination.
Health 3: I have seen a spring scale in the laboratory.
Teacher: If you are a conscientious person, you will find that there are too many scales in your life. Take a closer look at what these pointers point to in the picture and tell everyone how heavy the items are. (The courseware shows 102 page, example 2 is shown below)
Health 1: the weight of a bag of washing powder 1 kg.
Health 2: The child weighs 23kg.
Teacher: Please cooperate and communicate in the group, weigh the items with the mass of 1 kg, and weigh them by hand. Think about which items in life weigh 1 kg.
Students cooperate and communicate in groups, and teachers patrol to understand the situation.
Organize students to exchange reports, complete the second question of "doing" on page 103 of the textbook, and fill in the form. Design intention: Start with students' life, connect with life and be close to life, so as to shorten the distance between life and teaching materials, stimulate students' internal learning motivation, improve their interest in learning, and thus actively learn new knowledge.
3. Where is it? Fill in ">"
2 kilos? 2000 grams, 5 kilograms and 4900 grams
800 grams? 1 kg 2500 kg 3 kg
4. Judge right or wrong.
An egg weighs about 50 grams. ? (? )
Xiaoming is 7 years old and weighs about 2000 grams. (? )
1 kg iron is heavier than 1 kg cotton. (? )
One bag of salt is 500 grams, and two bags of such salt weigh 1 kg. (? )
Third, sum up and improve:
Teacher: Students, what have you learned from today's study?
Fourth, homework:
Mathematics teaching design for the second grade of the second primary school
Multiplication formula of 7:
Teaching content: the content on page 72 of the textbook;
1. Make use of students' existing knowledge, experience and analogy ability, let students experience the formulation process of the formula independently, understand the source of the multiplication formula of 7, and understand the significance of the multiplication formula of 7.
2. Master the characteristics of the multiplication formula of 7, memorize the formula, and gradually improve the ability to use the formula flexibly.
3. Through multi-angle practice, we realize that mathematics is around us and stimulate students' interest in learning mathematics knowledge.
Teaching process:
First, independent exploration.
1, Introduction
The teacher showed a picture made of a jigsaw puzzle.
Teacher: This is a pattern made up of puzzles by students. What are they spelling?
Teacher: How many puzzles does it take to spell a pattern? How many sevens are there? How to list multiplication formulas? Can you come up with a multiplication formula?
Teachers and students answer the blackboard together as follows:
1 7 is 7 1×7=77× 1=7. 17 equals 7.
Teacher: How many puzzles does it take to spell two patterns? How many sevens are there? What is the corresponding multiplication formula or formula?
The teacher continued to complete the corresponding blackboard writing.
Teacher: Like this, can students try to make up other multiplication formulas of 7 according to these seven patterns?
2. Formulation
Open page 72 of the textbook and try to fill it in.
3, the whole class communication
(1) Report and write it on the blackboard.
(2) According to the students' report, the courseware shows the multiplication formula of 7.
(3) check the students' learning situation.
Tell me which formula can represent the number of pieces of a puzzle with four patterns? What is the corresponding multiplication formula?
How many puzzles does it take to spell out six patterns? What is the multiplication formula used? Which multiplication formula can you come up with according to this multiplication formula?
What does the phrase "5735" mean?
Why can the formula "7749" only be used to calculate a multiplication problem?
Second, the memory formula
1. Just now, Qi Xin made up a multiplication formula of 7. Please clap your hands and read the formula together. After reading it, let the students recite the formula by themselves.
Teacher: Which multiplication formula of 7 do you think is easy to remember? Why?
The teacher tells the situation in the cartoon and asks the students to find the multiplication formula of 7 and use the associative memory formula.
Teacher: You see, these stories and sayings in life can also help us associate multiplication formulas.
What are the characteristics of the multiplication formula of 2 and 7?
From top to bottom, the first number in the formula is 1, the second number is 7, and the product is 7.
Teacher: Why does the product increase by 7 in turn?
Use the discovery to make students remember the formula again, and then play the password game.
Third, flexible use.
1, see the formula and say the formula.
7×3= 7×5= 7×6= 3×7+7=
7×4= 7×7= 7×2= 7× 1= 7×7-7=
2. Think about it. What are the things, phenomena and stories related to 7 around us?
(1) Points on ladybugs.
(2) Calculate the number of words in a poem
Quatrain
Two orioles sing green willows,
A line of egrets rose into the sky.
The window contains autumn snow in Xiling,
Mambo Wu Dong Wan Li Ship.
This poem is a classic poem read this week. Can you recite it? Students shoulder to shoulder.
Is there a 7 here? Do you know how many words there are in a poem? what do you think?
Teacher: Each sentence has seven words, so it is also called "seven-character poem".
Teacher: How many words are there in the topic 1 * * *? How to form?
(3) The first part
1 dwarf 1 hat, 7 dwarves and 7 hats;
1 Dwarf with 2 clothes, 7 Dwarfs with () clothes;
1 dwarf has 3 pairs of pants, and 7 dwarves have () pairs of pants;
1 pair of dwarf () shoes and 7 pairs of dwarf () shoes;
Mathematics teaching design for the second grade of the third primary school
Learning content: solving practical problems by multiplication and division. Learning objectives:
1, so that students can learn to solve the practical problems of two-step calculation according to the multiplication and division relationship.
2. Let students apply what they have learned and serve them well.
Preparation of teaching and learning tools: the items needed in Example 4 on Page 3/kloc-0 of the textbook.
Learning process:
First, guide the class by talking.
Do children like shopping? They like it, and then let them guess the prices of exercise books, pencil cases, balls, rackets, etc.
Second, explore new knowledge.
1, displays children's stores, and displays various commodities and unit prices.
2. Start shopping in groups of four.
(1) Tell me how much money you have and what are you going to buy? Talk about your shopping plan in the group.
(2) Group work and cooperation, some play the role of shop assistants and some play the role of customers.
(3) Students start shopping.
3. Communicate your shopping process in class. Show it in the form of performance.
Example:? A, 12 yuan can buy three cars.
I want to buy five cars.
C, how much should I pay?
D. Dealing with 20 yuan.
Ask the students who are performing to talk about how they worked it out.
12 ÷ 3 = 4 (yuan) 4×5=20 (yuan)
5. Ask another group to show their shopping process in front of the blackboard.
6. These groups communicate with each other.
7. Teacher-student summary.
Third, students independently complete the "doing" of 3 1 page. Then, according to the "do-one-do" diagram, the problems that can be multiplied and divided are put forward in two steps and answered each other.
Fourth, the whole class summarizes.