Drawing angles is based on learning how to use protractor, so that students can realize that protractor can not only draw angles, but also help students draw angles. The following is the teaching plan of the fourth grade mathematics corner diagram I compiled, hoping to provide you with reference and reference.
Wen Yi, a model teaching plan for fourth-grade mathematics corner painting
[Teaching objectives]
1, the angle of the specified degree will be drawn with a protractor.
I will draw some special angles with triangles.
[Teaching Emphasis and Difficulties]
1, the angle of the specified degree will be drawn with a protractor.
I will draw some special angles with triangles.
[Teaching Preparation] Everyone prepares a protractor and a triangle.
[Teaching process] 1. Draw an angle of a specified degree.
1. Try to draw an angle with a specified degree.
Ask the students to draw a 60-degree angle: How many ways can you draw?
2, communication, summary
Communicate in the group first, and then communicate the painting in the whole class.
How to draw with a protractor? What should I pay attention to? (pay attention to the number of inner and outer circles, and you can estimate it after painting. )
How to draw with triangles? What should I pay attention to? Only some special angles can be drawn with triangles. )
3. Draw an angle of 150 degrees.
How many methods can you use?
Second, give it a try.
1. Try it: Question 1. Students first measure the degree of the corner of the red scarf with a protractor and then draw it.
2. Think and discuss how many degrees you can draw with a set of triangles.
Homework: Exercise 2, 3
[Blackboard Design]
Draw corners
Draw an angle with a protractor and an angle with a special degree with a triangle.
[Postscript of Teaching] There are more than a dozen people who can't use the special angle of triangle. I asked the group leader who studied well to guide them. I believe it will be fine!
Wen Er, a model teaching plan for fourth-grade mathematics corner painting
Teaching content: Beijing normal university printing plate, unit 2, volume 7, fourth grade primary school mathematics, draw corners.
Teaching material analysis: This textbook focuses on learning how to use protractor, so that students can realize that protractor can not only draw angles, but also help us draw angles.
Analysis of the situation of this class and the characteristics of students: There are 19 students in this class, including 12 boys and 7 girls. The learning atmosphere in the class is more positive, and most students can study consciously. Only two students have some difficulties because of their young age and have a strong sense of cooperation.
Teaching objectives:
1, the angle of the specified degree will be drawn with a protractor.
2. I will use a triangle to draw some angles with special degrees.
Teaching emphasis: Draw an angle of a specified degree with a protractor.
Teaching difficulty: When drawing an angle with a protractor, the inner and outer circles are not divided.
Design concept:
Encourage students by recalling the use of protractor. The protractor can not only draw the angle of energy, but also help us draw the angle accurately. Would you like to try? Naturally transition to today's knowledge points. After that, give students a relaxed environment and enough time to acquire useful skills and methods in independent exploration. At the same time, draw and say the basic steps to cultivate students' language expression ability and logical thinking ability. Draw some angles with special degrees with triangles. Cultivate students' ability to solve problems flexibly.
Teaching process:
First, review the introduction.
1. Students draw any angle and measure the degree of the drawn angle.
The teacher patrolled and found problems.
2. Show the degree of mispronunciation in angle measurement, consolidate the angle measurement method and attract students' attention.
Second, the new lesson learning
1, Teacher: The angle was different just now. Can the group find a way to make the corners drawn by each student in the group equal?
Division patrol found that:
Some students in the group didn't do what they wanted to do, but still "went their own way" and drew themselves from the corner.
2. The teacher emphasized the requirements again:
Individual group: Draw angles with the same degree at the suggestion of the group leader: 35 degrees and 50 degrees. But the drawing method is different, and some students make mistakes.
Most groups: the students in the group found it faster to draw with triangles directly, so this method was adopted uniformly.
3. Angle drawing method
(1) Take 50 degrees as an example:
Health 1: drawing error
Student 2: Show me the correct picture!
Correct the problem when drawing corners:
A. point vertex.
B. draw an edge.
C. determine the other party. How to determine each other? Self-study book: P58 pages
(2) Using triangles to show the method of drawing corners.
4. The group draws the same angle again.
Requirements: Do not draw right angles, right angles, rounded corners and other special angles.
5. Consolidation exercises:
(1) Draw an angle as follows:
40 degrees 140 degrees
(2) Draw an angle of 70 degrees and an angle of 120 degrees on the point and ray respectively:
Third, draw a corner at the teacher's request:
1, draw a 60-degree angle (how do you want to draw? )
(Generally, some students draw with triangles, while others draw with protractors. )
Tell me which is more convenient.
2. Draw an angle of 75 degrees.
How do you want to draw it? )
(Generally, some students draw with triangles, while others draw with protractors. )
Tell me which is more convenient.
Draw an angle of 150 degrees.
3. Draw an angle of 15 degrees.
After finding that the two triangles could not be spelled out, all the students drew angles with protractors, and only one student drew an angle of 15 degrees by showing the protractor.
Show the method of "reducing the angle" with triangles.
4. Draw an angle of 100 degree.
Seeing the angle of 100 degree, many students use the method of spelling triangles. After a short time, they give up triangles and draw with a protractor.
Teacher: A triangle can only spell (subtract) special angles, and many angles need to be drawn with a protractor.
Fourth, class summary: What did you learn in this class?
The fourth grade mathematics corner diagram teaching plan model Wensan
Teaching objectives:
1, consolidating how to judge the parallelism and verticality of a straight line.
2, through practice to consolidate the use of protractor to measure the degree of the specified angle, draw the angle of the specified degree.
Emphasis and difficulty in teaching: I will measure the degree of the specified angle with a protractor, draw the angle of the specified degree, and judge the parallelism and verticality of the straight line.
Preparation before class: physical projection, protractor, triangle, round paper, rectangular paper
Class schedule: 1 class hour
Teaching process:
First, review the key points of this unit.
1, the characteristics and reading methods of lines, line segments and rays
2. Definition and drawing of parallelism and verticality.
3. Angle measurement and drawing
Second, practice.
1, the first question The picture below is a part of the map of Beijing. Please find two groups of parallel and vertical roads (let students talk about the method of judgment)
The second question is, which two roads are parallel near your school? Which two roads are perpendicular to each other? Students can draw a sketch.
3. The third question is to estimate first, and then measure the degree of the following angles. The side of the angle is not long enough to indicate the exact degree on the protractor. What should I do? (Extend a corner)
4. The fourth question
(1) How many degrees do you get by folding a circular piece of paper in half three times?
A, students try to do it, communicate at the same table, and then communicate with the whole class.
B, guide students to find that every time they fold in half, the angle they get is half of the original.
C, spread out the folded paper, how many degrees can you find on this paper?
Work in groups and draw a picture.
(2) Folding the angles of 45 and135 with rectangular paper allows students to operate independently first and then communicate with the whole class.
Third, review the angle measurement with a protractor.
Exercise 2, Question 3, Question 4: Let the students estimate the angle first, and then measure it with a protractor.
Fourth, use knowledge to solve problems:
1, Exercise 2, Question 5:
This is an operation problem, which allows students to find laws and solve problems in the process of operation. Let the students operate, discuss, find the rules and solve the problems by themselves.
2. Exercise 2 Question 6:
Ask the students to find the right angle, acute angle and obtuse angle in the picture through independent observation, and then communicate with their classmates.