Teaching plan design of the second grade mathematics "Understanding of Corner" by Jiangsu Education Press 1 teaching content;
84-85 pages under the second edition of Su Jiao Edition.
Teaching objectives:
1, find the angle according to the life situation, know the angle, remember the names of each part of the angle, and get a preliminary understanding of the angle.
2. Let students begin to draw and make corners, deepen the understanding of the diagonal, and compare the sizes of the corners, and experience the process of "perception-representation-abstract generalization".
3. In the process of understanding the angle, we can understand the close relationship between mathematics and life, learn methods in the process of exploring the angle, enhance the interest in mathematics learning and develop mathematical thinking.
Teaching focus:
Can find the angle from life, know the angle, and compare the angles correctly.
Teaching difficulties:
Understand that the size of the angle is related to the size of the edge opening.
Teaching preparation:
Student: activity angle, triangle ruler, two sticks.
Teacher: The movable angle, the triangular ruler, the whiteboard courseware and the cardboard are composed of two triangles with equal angles and one triangle with different angles.
Teaching process:
First, contact life and introduce new knowledge.
1. Import "Corner".
This is a photo of the stadium supermarket. What are the items in the picture? What shapes do they have? Although the shapes of these objects are different, there is a new figure hidden on their surfaces, which is the "corner" of the figure we are going to understand in this lesson. (Blackboard Title: Understanding Angle)
2. Find a corner of life.
Show the physical map: (five-pointed star). The teacher demonstrated the pointing method of the angle: the figure formed by the tip and the two straight lines on the tip is called the angle. Who would point at another angle on it like this? Then ask the students to take out their triangular ruler, find its corner and show it to your deskmate.
Second, contact life and know the angle.
1, find the angle.
Look at the three objects in this picture. Can you find the corners on them? Show scissors, triangle and clock face. The students pointed out. Please remove the corners from the picture and explain that these figures are all called corners. What features do you find on the corner? (Courseware demonstration)
2. Know the name of the corner.
Each corner consists of a sharp point and two straight lines. We call this scream the apex of the corner, and two straight lines are called the two sides of the corner. We usually draw an arc from one side of an angle to the other side of the angle and make a mark to represent the angle. Now, look at these angles. How many vertices and edges do they have? Conversation between deskmates.
3. Draw corners.
Can you draw a corner? The teacher demonstrated drawing a corner. Draw a little first, then draw a straight line from the vertex, and then draw a straight line from the vertex in different directions (the lengths of the two straight lines are different) to mark the vertex and edge of the angle.
pinnacle
edge
edge
4. Touch angle, feel angle
Teacher: Just now, the students said that there are angles on the triangle. Please take out your triangular ruler, find one of the corners, and touch its vertex and edge with your hands. How do you feel?
Step 5 find a corner.
If the teacher gives you two sticks, can you make a corner? Try to point out the names of the parts of the angle you take. Q: What are horns made of? Will you close your eyes and draw an angle in the air with your little hand? The teacher drew a corner with its opening facing in different directions on the blackboard.
6. Determine the angle.
I heard that we know Jiao, and there are guests coming to class, all vying to say that they are Jiao, right? Please make a judgment, it is the vertex and edge of the angle, not the angle.
7. Count the angles
What is the key to judge whether a figure is an angle? A corner is actually a member of a plane figure. Now please count the corners in the picture below. Please mark the corner first, and then fill in the blanks. (Think about doing the second question) After the students finish, give feedback on the whiteboard and evaluate collectively.
8. Find a corner of life.
The corner is actually around us. Please carefully find out which objects around you have angular surfaces and tell your deskmate. It seems that corners are really everywhere. As long as children have a pair of math eyes, they will find more corners.
Third, explore independently and compare the angles.
1, show the demonstration of activity angle. The children looked at the magic horn in the teacher's hand. If you pull the two sides of the horn apart, it will become bigger, and if you close the two sides of the horn, it will become smaller. Will you change your perspective with the teacher? How to make the angle bigger and how to make the angle smaller? Blackboard: There are different angles.
2. Thinking: What does the angle have to do with it? Communicate at the same table and complement each other after reporting.
The change of angle size is often encountered in our life. For example, when we do manual work, the angle will decrease when we close the scissors, and it will increase when we turn on the fan in summer. Courseware demonstration
3. compare it.
We just found the corner on the clock face. The hour hand and minute hand on the clock face keep turning, and the two hands form angles of different sizes. (Showing three clock faces) Can you see which angle is the largest and which angle is the smallest? how do you know
There are two horns. Do you know which corner is bigger and which corner is smaller?
Why? How to prove it? (Courseware demonstrates overlapping method). What about figure 1 and figure 3? What does the angle have to do with?
Fourth, return to life and expand new knowledge.
Today, we met Jiao. Can you introduce this new friend to everyone? The courseware shows pictures of the corner of the campus. After class, find out which objects in life still have horns on their faces. Tell your classmates.
Blackboard design:
Cognitive angle
pinnacle
edge
edge
A corner has a vertex and two sides.
Trumpets have sizes.
Teaching plan design of the second grade mathematics "Angle Understanding" of Jiangsu Education Press 2 Teaching purpose;
1, knowledge and skills: looking for an angle, understanding an angle and initially understanding an angle in a specific life situation.
2. Process and method: Draw and make corners by hand, deepen the understanding of diagonal lines, and compare the sizes of corners.
3. Emotion, attitude and values: in the process of understanding the angle, we can experience the close relationship between mathematics and life, enhance our interest in mathematics learning, and learn methods in the process of exploring the angle.
Teaching focus:
Can find the angle from life, know the angle, and compare the angles correctly.
Teaching difficulties:
Make students realize that the size of an angle is related to the size of both sides of the angle, but not to the length of both sides of the angle.
Teaching preparation:
Teaching AIDS: activity angle, triangle, teaching courseware, rectangular paper.
Learning tools: triangle, ruler, marker, rectangular paper.
Teaching process:
First, create situations and introduce new lessons.
Teacher: Children, today the teacher brought some graphic friends to you. Let's go and have a look. Who are they?
Health: rectangle, square, circle, triangle.
Teacher: The children did a good job. There is a friend hidden in these figures. Do you want to know this friend?
Health: Yes.
Teacher: Let's see who this friend is. (Courseware demonstration)
Teacher: Do you know each other? Students all say it's a corner, so what kind of figure can be called a corner? Today, we will meet Jiao.
Courseware presentation theme: cognitive perspective
Second, contact life and explore new knowledge.
(A) Angle-intuitive perception angle
1, Teacher: See if there are any corners on these objects? Who wants to talk?
(speaking)
2. See what objects around you also have horns? (speaking)
Angle of understanding
1 Touch perception angle.
Teacher: Just now, the students said that there are angles on the triangle. Please take out your triangle, find one of the corners and touch it with your hand. How do you feel?
(Life activities, teacher's guidance and demonstration)
Know the vertex and edge of an angle.
Teacher: What does it feel like for students to touch sharp places?
Health: prick the hand.
Teacher: Let's call this place the apex of the corner. Do the three figures on the screen have vertices?
Teacher: What does it feel like for students to touch both sides of the corner again?
Health: flat and straight.
Teacher: We call these two flat and straight lines the two sides of the corner. Do the three figures on the screen have straight edges?
Teacher: Now, on the same table, point out the vertices and corners of the objects around you to each other. (Pay attention to the angle pointing method: first point to the vertex, and then point to the edge. )
Teacher: Let's see how many vertices and sides there are in these three corners.
Summary: A corner has a vertex and two sides.
Teacher: Children, now that we know Jiao, whether we can become good friends with Jiao depends on your performance. (Courseware demonstration)
(1) Think about doing the 1 problem.
Which of the following figures are corners and which are not?
Students judge independently and point to the stage. Foundation: A corner has a vertex and two sides, and both sides are straight.
(2) Find a corner and think about doing the second question.
Students fill in the blanks independently and tell the process and result of thinking. Not only should you tell the number of angles, but you should also ask where each angle is, and if necessary, point to the vertices and sides of the angle. (properly point out how many angles there are in several polygons. Note: Usually we draw a small arc on both sides to represent this angle. Some corners will be marked with right-angle symbols, which you will learn later. )
(3) Draw corners
Teacher: Can you draw a corner on the paper? How to draw a corner?
Teacher: (Demonstrating to draw a corner) Draw a little first, then draw a straight line from the vertex, and then draw a straight line from the vertex in different directions. In this way, there is an angle composed of two sides of a vertex, which we represent by a small arc.
Health: Practice drawing corners on paper.
Third, do it by hand and compare the angles.
(1) Have some fun
Teacher: It seems that you have made friends with Jiao. Then can you extend both sides of the corner you just drew? How long can you paint? Student activities, teacher guidance.
Teacher: Guess, has the size of the horn changed?
(2) Relative scale
Teacher: The students draw the corners very well. The teacher also brought two horns today. Listen, the children are talking. (courseware demonstration).
Teacher: After watching the animation, that is to say, the angle between the big three-angle ruler of this shape in the teacher's hand and the small three-angle ruler of the same shape in your hand is-(students answer, teachers and students compare).
Teacher: Since the size of the angle has nothing to do with the length of the side, what does it have to do with it?
Teacher: (showing the courseware and demonstrating the opening process of scissors) Can you tell me what the angle is related to?
Teacher: Children see a movable horn in the teacher's hand. Who will make it bigger and smaller? (name operation, teacher's guidance: pull apart the two sides of the angle, the angle will become larger, and close the two sides of the angle, the angle will become smaller. )
Teacher: Now, can you fully talk about what the size of the angle is related to?
Summary: The size of the angle has nothing to do with the length of the side, but with the openings on both sides of the angle. The bigger the opening, the bigger the angle, the smaller the opening and the smaller the angle.
Exercise: Think and do the third question. Now there are three clock faces here. Can you see which angle is the largest and which angle is the smallest? what do you think?
(3) 10% discount
Folding: Take a piece of paper and use it to fold corners of different sizes.
Inspiration: What can I do to make a bigger corner? What can I do to make a smaller corner?
(4) Compare with each other
Teacher: Take out your folded corner and compare it at the same table to see who has the bigger corner and who has the smaller corner. How do you compare?
The courseware guides the students to overlap the vertex and an edge respectively, and you can see which angle is larger. )
(health activities)
(D) Thinking expansion
Courseware demonstration:
? How many angles are there in the digital map? When you cut a rectangle, how many corners are left? Can you draw and tell the change of the number of angles?
Fourth, role-playing, class summary
Teacher: In this class, let's get to know each other. Students, please consider yourself as a corner and introduce yourself! Hello, I'm Jiao. I have one _ _ and two _ _.
Draw me first () and then ().
My size has nothing to do with (), but with ().
Verb (abbreviation of verb) practice:
Can a magnifying glass enlarge the angle?