course content
(1) Understand the meaning of negative numbers
P. 1, 2, complete the exercises on page 3 and the questions in 1/~ 5.
Teaching objectives
1, understand the background of negative numbers in real situations, understand the meaning of positive and negative numbers and zero, master the representation method of positive and negative numbers, and know that 0 is neither positive nor negative.
2. Master the reading and writing methods of positive numbers and negative numbers. And can read and write correctly.
3. Experiencing mathematics is closely related to daily life, and some successful experiences are gained to stimulate students' interest in mathematics.
Teaching focus
The difficulty in teaching is to understand the meaning of positive and negative numbers and zero in real situations.
Describe the phenomena in life with positive and negative numbers.
Exploration, discussion and exchange of teaching methods and means.
Teaching preparation related courseware.
teach
study
get through
travel
First, dialogue import:
Do you know what to learn in this class through review? (blackboard writing: negative number)
What numbers have we known before? (natural numbers, decimals, fractions)
Give examples respectively. Point out: the most common is natural numbers, and decimals have special marks? Decimal point? There is a special mark on the score. Do you know any special signs of negative numbers? (minus sign, similar to subtraction)
Second, the learning example 1:
1, Dialogue: Do you know the highest temperature today? Can you find this temperature on the thermometer?
2. Description: Introduce the thermometer: (1)℃, ℉, which is our domestic unit, namely℃; ℉ is Fahrenheit, which is used in Europe and America. (2) With 0 as the boundary, the temperature above 0 means above zero, and the temperature below 0 means below zero. (3) scale. Pay attention to how many degrees the big grid and the small grid represent respectively.
3. Student identification: Find the scale indicating 35℃ on the thermometer.
Dialogue 4: Do you know when it is 0℃? (mixture of water and ice)
5. Dialogue: Do you know the lowest temperature in Jiangdu for one year? Can you find it on the thermometer?
6. Know the temperature of three cities in the textbook.
7. Discussion: Talk about your feelings about the temperatures in these three different cities.
8. Try to read and write.
9. Question: Is +20 the same as -20?
Third, study example 2:
1, Dialogue: Introduce the situation map in the textbook.
2. Panel discussion: What do you know?
3. The whole class reports and exchanges.
4. To sum up: the altitude is usually based on sea level, and how many meters above sea level is how many meters above sea level; How many meters below sea level is how many meters below sea level.
Fourth, induction:
1, Conversation: Through example 1 and example 2, everyone should know the usage of positive and negative numbers in life. Can you give me an example?
2. report and exchange.
Verb (abbreviation for verb) consolidation exercise
1, guide the completion of the second moths? Practice? . (Focus 0)
2. Finish the first exercise. (Emphasize that negative numbers include integers, decimals and fractions)
3. Finish the second exercise. By the way, the situation of these two lakes.
3. Complete the third exercise.
4. Complete the fourth exercise.
6. class summary: ask questions. What did you learn from today's study? What do you want to say to everyone? Review after class
Preliminary understanding of negative numbers in blackboard writing design (1)
20℃ above zero can be recorded as? +20℃? +20 is pronounced +20.
20℃ below zero can be recorded as? -20℃? -20 is pronounced negative 20.
Reflection after class
Lesson 65438
Total () class hours
Learning Mathematics (Book 9) The lesson preparation teacher cares about the teaching time, week, month and day.
Examples 3 and 4 of teaching content p.3 and 4, complete exercise 7~ 10 and exercise 1 on page 5.
The teaching goal is 1, so that students can apply negative numbers in real situations such as profit and loss, income and expenditure, fluctuation, increase and decrease, and two movements in opposite directions, and further understand the meaning of negative numbers.
2. Experience the close relationship between mathematics and daily life, and stimulate students' interest in mathematics.
Teaching focus
Teaching difficulties should use positive numbers and negative numbers to represent quantities with opposite meanings in daily life.
Experience two quantities with opposite meanings.
Exploration, discussion and exchange of teaching methods and means.
Teaching preparation related courseware.
teach
study
get through
travel
First, dialogue import:
1, dialogue: We learned negative numbers last class. Please say in your own words what kind of numbers are negative?
2. Dictation: A few positive numbers and a few negative numbers.
Second, learn new lessons.
1, learning example 3
Dialogue: Positive and negative are antonyms, and there are many opposite changes in life. It can also be represented by positive numbers and negative numbers respectively.
Student example (possible):
(1) Income and expenditure: If the teacher got the salary of 1500 last month, to emphasize? Income? Can I remember this? + 1500? I spent 300 yuan on clothes. How could I remember? Why? Ate 500 yuan. How do you remember?
(2) Transfer in and out: In this new semester, our class will transfer in 1 person and transfer out 3 people. What do you mean?
(3) Getting on and off: (Question 10), write down the situation of each stop in turn, and let the students say what each stop means. Especially? 0? ; You can also combine a stop to let students talk about 3 +8? In fact, what has changed in the number of people?
(4) Go upstairs and downstairs:
Auxiliary floor, representation of the first room, etc. Supplement: A building may have a positive floor or a negative floor. Will there be a floor zero? Why?
(5) Go east and go right: There are four common directions, east and west are opposite directions, and south and quilt are also a pair of opposite directions. If you want to walk 5 meters east, it's marked as +5 meters, then walk west 10 meters. How do you remember? what do you think? What does+10 meter mean? Why?
If+10 means going south 10 meters, then? What does 10 meter mean? what do you think?
Compare this question with the previous one: the positive and negative numbers in front generally mean increase or decrease, while the positive and negative numbers only mean the opposite.
Summary: Many opposite meanings in life can be represented by positive numbers and negative numbers respectively.
Students teach themselves the table on the third page of the textbook.
Tell me what you found on the table.
The whole class reports and exchanges.
2. Teaching? Try it?
Dialogue: Can you complete the table in the book?
The whole class reports and exchanges.
3. Teaching Example 4
Students teach themselves.
Question: What did you learn through self-study? (Both started at school)
Note: regarding the direction, people generally express the distance to the east as a positive number.
4. Teaching? Practice?
The students study hard.
Q: What do you know?
Summary: Income and expenditure can also be represented by positive and negative numbers.
Third, consolidate the practice.
1 Finish the exercise 1 Question 5. (After each form is completed, the whole class will report and communicate.)
2. Complete question 6 of exercise 1.
Talk to each other in groups.
3. Complete question 7 of exercise 1.
Fill it out yourself.
Questions: -2 and -4. Which is closer to 0?
4. Complete the exercise 1, question 8.
Let's talk in the group first.
Question: What do you find from the table?
Fourth, the class summary
Talk: What are you most happy about today's study?
Review after class
Preliminary understanding of negative numbers in blackboard writing design (2)
Profit and loss, income and expenditure, direction, lifting, getting on and off the bus can all be expressed by positive numbers and negative numbers.
Reflection after class
second kind
Total () class hours
Learning Mathematics (Book 9) Lesson Preparation Teacher Ding Haijian teaches on week, month and day.
Teaching content 1, calculation of parallelogram area (No.7? 8 pages)
Teaching objectives 1. On the basis of students' understanding, mastering the calculation formula of parallelogram area can correctly calculate the area of parallelogram.
2. Develop students' concept of space through the operation, observation and comparison of graphs, and make students know the application of transforming thinking method in studying parallelogram area.
3. Cultivate students' ability to analyze, synthesize, abstract, summarize and solve practical problems.
Teaching focus
Difficulties in teaching Understanding and mastering the area formula of parallelogram.
Understand the derivation process of parallelogram area formula.
Exploration, discussion and exchange of teaching methods and means.
Teaching preparation related courseware.
teach
study
get through
Cheng Yi, review of imports:
1, tell me about the floor plan you have learned.
2. Which of these figures has the area you want?
Second, explore new knowledge:
1, teaching example 1:
(1) Draw 1 in the example 1.
Requirements: Are the areas of the following two figures equal? Discuss in the group how you will compare the areas of these two figures. (Students organize communication after group activities)
(2) Give the second set of graphs in the example 1.
Requirements: Can you compare the sizes of these two diagrams without the previous method? (Students communicate, and the teacher emphasizes it appropriately? Transformation? The method. )
(3) Reveal the topic:
Teacher: Today, we use the knowledge we have learned to apply the mathematical thought of transformation to study the area calculation formula of new graphics. Shall we study it today? Calculation of parallelogram area? . (blackboard writing topic)
2, teaching example 2:
(1) Display parallelogram
Teacher: Can you find a way to turn this parallelogram into a learned figure?
(2) Students' operation and teachers' patrol guidance.
(3) Students communicate the operation situation.
The first type: ① Cut a right triangle on the left along the height of the parallelogram.
② Translate this triangle to the right.
(3) Overlap to the hypotenuse.
The second type: ① Cut the parallelogram into two trapezoids at any height.
② Move the left trapezoid to the right.
③ The hypotenuse coincides.
(4) Use courseware to demonstrate and summarize.
Teacher: You can turn a parallelogram into a rectangle, cut any manuscript along it and then translate it.
(5) Group discussion:
① Is the area of the converted rectangle equal to the area of the original parallelogram?
② What is the relationship between the length of rectangle and the base of parallelogram?
③ What is the relationship between the width of rectangle and the height of parallelogram?
(6) Students summarize and form the following blackboard writing:
Area of rectangle = length x width
Area of parallelogram = base x height
3, teaching example 3:
(1) Question: Can any parallelogram be transformed into a rectangle? Can you deduce the area formula of parallelogram? Please cut out any parallelogram from page 1 15 of the textbook, first convert it into a rectangle, then find out the area and fill in the table below.
Converted rectangular parallelogram
Length (cm) width (cm) area
(Square centimeter) Base (centimeter) Height (centimeter) Area
(square centimeter)
(2) Students' operation and feedback communication.
(3) The formula for representing the surface with letters: S = a h (blackboard writing)
Third, teaching? Try it?
1, look at the topic together.
2. Students try.
3, teachers and students * * * with evaluation.
Fourth, summary:
Teacher: What did you gain from today's study?
5. Student's homework: P Practice is on page 8. Review after class
Calculation of parallelogram area in blackboard writing design
change
Graphics that have been learned, new graphics
Cutting and mending, cutting and spelling
Because the area of a rectangle = length? extensive
So the area of parallelogram = bottom? high
Reflection after class