Three Views Lecture Draft 1 First of all, lecture materials
1, content of this lesson:
In the compulsory education stage, the learning content of mathematics includes "number and algebra", "shape and geometry" and "synthesis and practice". This lesson will explain "graphics and geometry". According to the requirements of the syllabus, the content of this course needs to draw the front view, left view and top view of a straight prism, a cylinder, a cone and a ball; Can judge the view of simple objects and describe simple geometry according to the view.
The teaching focus of this lesson: understand three views and master the drawing method of three views.
The teaching difficulty of this lesson is the mutual transformation between geometry and its three views.
2, the position in the textbook:
"Three Views" is the teaching content of the second section of Chapter 29 "Projection and View" in the second volume of the ninth grade of People's Education Press. Through the study of this lesson, we will lay a foundation for further study of space geometry in senior high school.
Second, students.
1. Students' existing knowledge base includes: parallel projection, orthographic projection, central projection and structural features of space geometry.
2. The students in this class have high enthusiasm for learning, strong curiosity and certain inquiry ability, but their abstract thinking ability is weak, so they should make a breakthrough in classroom teaching.
Third, say the goal.
1, through exploration and study, understand the concepts of view and three views, master the drawing method of three views, and be able to convert between three views and geometric figures.
2. I think that observing the same object from different directions may lead to different results and cultivate students' comprehensive observation ability. Through the analysis of the three views, the basic drawing method of the three views is mastered by group inquiry, which promotes the clarity of students' thinking activities and improves their cooperative inquiry ability.
3. Only through three views can an object be determined, and multi-angle analysis is needed to inspire students to understand the problem.
Four. Oral English teaching methods and learning methods
1, teaching method:
According to the teaching concept of the new curriculum, students are required to be the center, and teachers should pay attention to guidance and inspiration. Therefore, discussion and experiential learning are adopted in the teaching process, so that students can actively participate in classroom teaching activities and grasp the key points of learning through teacher-student interaction and student-student cooperation. Because the knowledge of this course is abstract and students' abstract thinking ability is weak, intuitive demonstration is used to break through the difficulties of abstract knowledge in the teaching process. For simpler theoretical concepts, teachers adopt the teaching method to ensure the efficiency of classroom teaching.
2. Learning methods: In line with the student-oriented teaching philosophy, in order to let all students participate in the classroom and become the "protagonists" in the classroom, and also to cultivate students' cooperative inquiry ability, group discussions and inquiry learning are conducted when learning the three views of painting.
Fifth, talk about the teaching process.
1, import new knowledge:
Use the ancient poem "Tixilin Wall" to introduce it (horizontally, the mountain side becomes a peak, and the distance is different).
The design aims to cut into the theme and stimulate interest in learning. It also shows that disciplines are not isolated and have their mutual benefits, and mathematics can also be full of literary colors.
2. Explain the concept of "view"
The concept of "orthographic projection" learned in the last lesson is extended to the concept of "view".
The design intention is to combine new knowledge with old knowledge, establish the connection between knowledge, and make it easy for students to understand.
3. Show the application of three views in life and engineering design with pictures, and guide students to find that an object can be determined by three directions of views, thus leading to the study of three views.
The design aims to make students feel that mathematics comes from life, stimulate students' interest in learning mathematics, and guide students to discover the composition of the three views.
4. Explain the formation process of three views through intuitive animation demonstration, and explain the concepts of "front view", "left view" and "top view" at the same time; It shows the derivation process of positional relationship (long alignment, high alignment and equal width) and dimensional relationship among three views.
Students' abstract thinking ability is weak, so it is convenient for students to understand knowledge by using intuitive animation demonstration to complete this teaching content.
5. The key content of this lesson is to master the three-view drawing method of simple geometry, and complete the study of key content through group cooperation and inquiry. Divide the students into ten groups, each with 4-5 people. Distribute the physical models of "quadrangular prism", "triangular prism", "cylinder", "cone" and "sphere" to each group and explain the task requirements to the students.
Activity Task: Team members discuss and explore how to draw three views of a three-dimensional map. Five minutes later, choose one group from the two groups that drew the same three-dimensional diagram, draw three views discussed by the group members on the blackboard, and the other group will carefully observe and evaluate in the process.
According to the three views drawn by students, guide students to summarize the steps and problems that should be paid attention to in drawing three views (orthographic projection, location finding and sizing).
The teacher focused on the details of drawing three views, such as using dotted lines to represent invisible edges, and the determination of dimensions corresponds to the real object one by one (rigorous), and summed up the method of drawing three views of geometry (the front view and left view of cylinder are rectangular, the top view of cylinder and cone is circular, but there is a black spot in the middle of the top view of cone, and the top view of sphere is circular).
Design intention drawing three views is the teaching focus of this lesson. On the one hand, group cooperative inquiry can deepen students' understanding of this knowledge point, on the other hand, it can cultivate students' ability of cooperative inquiry.
6. In 6.PPT, the front view, front view+left view, front view+left view+top view are presented one by one by backward method, so that students can tell the corresponding geometric figures, train their conversion ability from view to stereoscopic view, and further explain that describing a stereoscopic figure requires three views.
The transformation between design intent geometry and three views is the difficulty of this lesson. It is easy for students to accept the method of judging geometry from three views step by step by using reverse reasoning.
Three views of the lecture notes 2. Speaking of teaching materials
1, teaching material analysis:
General technology course is an all-encompassing comprehensive subject. It involves physics, chemistry, biology, mathematics, fine arts and other disciplines. The current provincial version of "Reading and Painting" in senior high school labor technology market edition has many connections with mathematics, physics and fine arts. The section "Formation and Projection Law of Three Views" is the teaching content of the first chapter and the fourth section of "Understanding and Drawing". The teaching content of this section is based on students mastering some basic laws of drawing, the use of drawing tools and supplies, and the basic knowledge of orthographic projection and view. In order to fully express the size of the object, this section arranges the contents of three views. Three views are closely related to orthographic method, and its theoretical basis is orthographic method. Three-view is the core content of mechanical drawing and the basic method to express the shape and size of a three-dimensional object (machine body). The sectional view, part drawing and other contents to be learned later are based on three views, so the teaching of this section plays an extremely important role in the first chapter and even the whole mechanical drawing learning.
Second, talk about teaching objectives
1, ideological and moral goals:
Draw pictures in strict accordance with drawing standards, cultivate students' rigorous and meticulous style of study, and enhance their ability to help each other and coordinate their work. Correct the attitude of practical operation.
2, physical and mental health goals:
Cultivate students' patient and meticulous operating habits, pay attention to the coordinated operation of eyes, hands and brain, and enhance safety awareness.
3. Aesthetic goal:
Apply theoretical knowledge to practice, create beauty in practice, pay attention to the beauty of operating environment and pursue the beauty of model making.
4. Basic knowledge objectives:
Let students master the formation and projection law of three views, and use the knowledge of three views to understand the three views of an object (body) in combination with the three-dimensional diagram.
5, operation skill goal:
According to three views and three-dimensional drawings, three-dimensional models can be made flexibly by cutting, digging and sawing.
Third, talk about teaching design.
1, teaching focus:
The focus of this teaching should be the formation of three views and their corresponding position, projection and orientation relations with objects.
2. Teaching difficulties:
How to understand three views by combining them?
3, the combination of education:
Through the formation of the three views and the study of the projection law, students' spatial imagination is cultivated, and through the production of models, students' ability to integrate theory with practice and hands-on operation is cultivated. Make a model through two people's cooperation, enhance students' ability to cooperate with each other, cultivate a good style of study, and be careful.
4. Selection of teaching methods:
According to the content of this lesson, combined with the students' reality, the basic knowledge is explained by teaching method. Demonstrate the formation and projection law of three views with multimedia animation, and reveal its formation essence. Consolidate the theoretical knowledge taught by practical methods, combine theory with practice by practical methods, and further deepen the understanding of the three views, thus breaking through the teaching difficulties and allowing students to solve problems independently in practice by heuristic teaching methods.
5, learning guidance:
A, careful observation: guide students to carefully observe the animation demonstration and the teacher's physical demonstration, and understand the formation and projection law of the three views.
B, positive thinking: explain the demonstration with the teacher, think about the formation and projection law of the three views, and understand their essence.
C. Seriously sum up bold practice: actively cooperate with teachers' activities, conscientiously sum up bold practice, combine theory with practice, and experience theory in practice.
Fourth, talk about teaching ideas.
1, learning situation analysis:
According to the arrangement of teaching materials and teaching process, before this class, students have learned the basic laws of drawing, mastered the correct use of drawing tools and supplies, learned the orthographic method and view, and understood the basic characteristics of orthographic method and the concept and characteristics of view. However, how to express the exact shape and size of an object scientifically and generally remains to be studied this time. The front view and orthographic projection method have a great foreshadowing effect on the study of this course, which is very beneficial to students' understanding of the three views.
2. Teaching arrangement:
This teaching is divided into two classes. The first lesson explains the formation and projection law of three views and carries out drawing exercises of three views. In the second class, according to the three-dimensional diagram and the three-dimensional view, let students make three-dimensional models to further strengthen the relevant knowledge of the three-dimensional view.
B, students practice in pairs, reasonably divide their work, and cooperate with the creative mode, so that the collective wisdom can be brought into play, the spirit of cooperation can be embodied, and the creative effect can be further improved.
Notes on Three Views 3 I. teaching material analysis
1, the position and function of teaching materials
"Three Views" is the content of the first lesson in the second quarter of Chapter 29 of Grade 9 of New People's Education Publishing House. It is taught after learning the structural characteristics and projection of space geometry. Three views are the representation of space geometry and one of the foundations of solid geometry. Learning three views well is conducive to cultivating students' spatial imagination and geometric intuition, cultivating students' interest in learning solid geometry, and laying the foundation for subsequent study in senior high school. So I deepen my understanding of the concept of three views from the perspective of projection, and draw three views of simple geometry as the focus of this lesson.
2. Content and structure of teaching materials
The teaching content of this lesson first introduces the concept of trying by observing planes and dictionaries from different angles, and then analyzes the formation principle, position and size relationship of three views, so that students can fully understand them. Then, taking drawing a simple geometric model of three views as an example, the drawing method of three views and the essentials to be mastered are expounded in detail.
3. Design of teaching objectives
Second, knowledge and skills:
1, can identify three views of simple objects and understand the concepts of front view, top view, left view and three views.
2. Understand the dimensional relationship between various views; Long alignment, high alignment and equal width.
3. I can draw three views of simple geometry such as straight prism.
Third, the process and method:
Feel that observing the same object from different directions may lead to different results, and cultivate students' comprehensive observation ability.
Emotional attitudes and values:
1, the method of cultivating students' autonomous learning and cooperative learning, so that students can discover mathematics from life.
2. In the process of applying mathematics to solve life problems, taste the joy of success and stimulate students' enthusiasm for applying mathematics.
Fourthly, analyze the key points and difficulties of teaching.
Teaching focus:
1, deepen the understanding of the concept of three views from the perspective of projection.
2, can draw three views of simple geometry.
Teaching difficulties:
1, understand the sublimation of the three concepts.
2. Draw three views of simple geometry such as triangular prism correctly.
An analysis of verb (verb's abbreviation) students' situation
Students learned orthographic projection, parallel projection and orthographic projection. This lesson mainly studies three views based on orthographic projection. The ninth-grade students have strong observation, operation and guessing abilities, but their spatial imagination ability is still weak, and their thinking lacks universality, agility, rigor and flexibility. So the difficulty of this lesson is to sublimate the understanding of the concept of three views and draw the three views of regular geometry correctly. To achieve the breakthrough of difficulties, the key is to fully mobilize students' learning initiative, guide and inspire students to use their eyes, brains, hands and mouths by creating problem situations in teaching activities. Let students carry out independent inquiry learning in a state of rich activities and positive thinking, guide the process of cooperation, and make students develop in a direction conducive to knowledge construction.
Sixth, preparation before class
Teacher preparation: projector, courseware, geometric model (cuboid, triangular prism, cylinder, etc. )
Students prepare: textbooks, rulers, compasses and exercise books.
Seven, the classroom structure design
According to the teaching requirements of "autonomy-cooperation-inquiry" in the curriculum standard, this course is characterized by abstract knowledge and huge thinking. The teaching methods I use are intuitive teaching method, guided discovery method and discussion and communication method.
Eight, teaching media design
Make full use of the advantages of multimedia-assisted teaching. According to the needs of teaching, two pictures are introduced into the topic to stimulate learning interest. The orthogonal projection of a cuboid with multimedia is used to get three views, and the process of getting the main view, the left view and the top view is displayed intuitively, so that students can understand the characteristics of the three views more intuitively and vividly. In order to break through the difficulties, the acquisition process of three views of multimedia demonstration cube is used to make students understand the drawing method of three views smoothly, so as to achieve the unity of teaching media, teaching objectives and content.