This is an in-class class rather than an open class. There was no audience, no visitors, no evaluators, so there was no performance. I have told this lesson for more than ten times. It can be said that the key and difficult points of this lesson and the logical relationship between knowledge points have long been clear in my mind. I can speak fluently without textbooks or lesson plans. However, although I am very proficient in the content of this course, I will prepare lessons carefully before each class, because the more times I teach, the less I dare to take my textbook to class, just like an old driver with many years of driving experience, the longer I drive, the more careful I am. I have thought about this question many times. Why am I getting more and more serious in class? Because, with the increase of teaching experience, I pay more and more attention to inspiring students' thinking in class, rather than simply "memorizing" the knowledge in textbooks to students. Now think about the students I taught a few years ago. In class, I brought knowledge, but I didn't touch their hearts and inspire their thinking well. What a pity! ), in teaching practice, I gradually formed a point of view: what you said is important. If you can't enlighten students' thinking and touch their lives in class, then for him, your teaching activities are as futile as an insurance salesman who can't meet a customer who really wants to buy.

Classroom is the main place for students to learn, and the effect of students' listening in class directly depends on their concentration and participation in thinking. So I don't think I have been there many times before class, so I can talk with my textbook. But from how to quickly grasp the attention of students and inspire their thinking. I can realize more and more now that the teacher's lesson preparation is not copying a lesson plan book to cope with the school inspection, but your unique "teaching design" for each lesson. Design should be creative. Although many people in China are teaching this lesson, you are different from anyone else. What is said in the textbook is all dead knowledge. If you can't catch students' attention in class and inspire their thinking, the conclusive things in the textbook. The courseware I used in class was saved several years ago, and it will be revised every time I use it, because the same content will have different ideas every time I speak. Perhaps the creativity of teaching activities is reflected here. Therefore, I say that this kind of class, which happens every day, is the most responsible class for students, and it must not be a casual class.

First, attract students' attention through "interesting introduction"

Making the classroom interesting has always been my ideal classroom model, and every class I take (especially the new class) strives to be interesting. I think a great advantage of interesting class is that it can attract students' attention immediately after the bell rings, and focus students' eyes on the inner tube I want to lecture.

The main content of the course "Plane Mirror Imaging" is to explore and evaluate the characteristics of plane mirror imaging through an experiment, and to explain the phenomena that students see when looking in the mirror every day in their daily lives with physical laws. In order to attract students' attention from the beginning, I first put two pictures in the courseware. The first one is a photo of Pig Bajie in Journey to the West, and the second one is a photo of Pig Bajie looking in the mirror. The students were immediately attracted by the image of Pig Bajie. Many students laughed when they saw the second picture. I know that most of my classmates' attention has been attracted. Then I went on to ask:

Who can say a xiehouyu from the second picture?

Many students raised their hands.

Then they almost said in unison, "Look in the mirror, pig, it's not human inside and outside."

I then asked, "Who can tell me why pigs look in the mirror and why they are not people inside and outside?" Who can explain? "

The question seemed a little sudden, and the whole class was silent.

The last classmate said, "Because he is a pig looking in the mirror."

Laugh again.

The time has come, and students' thinking has been enlightened.

I went on to say, "I don't think there should be laughter now, but there should be applause." This classmate is right. Pig Bajie looks in the mirror, and the image of pig Bajie appears in the mirror, so it is pig Bajie inside and outside, not people. If Pig Bajie looks in the mirror, it means that this mirror is not a flat mirror, but a magic mirror. "

Applause!

This is the end of Introduction to Fun. Next, we should inspire students' thinking and let them participate in the classroom by thinking about problems. I have always believed that a good classroom should have at least two dimensions, the first is interesting and the second is enlightening. Then I let the students look at some pictures of looking in the mirror, and then give them five minutes to preview the contents of the textbook, and find out the characteristics of flat mirror imaging described in the textbook in combination with their own observations when looking in the mirror in daily life.

Third, "inspiring thinking" begins with questioning the conclusion in the textbook.

Under normal circumstances, the day before I talk about each new class, I will leave an assignment: preview the next class at home. Because of the mid-term exam last week, I didn't leave this homework, so I can only leave time for students to preview in class. I have a set of methods on how to guide students to preview before class and review after class, which I will summarize slowly in future articles. Five minutes passed quickly, and many students browsed the content of this lesson and got a general understanding of the content to be talked about in this lesson. But no matter what the effect is, students can always find sentences describing the imaging characteristics of flat mirrors in textbooks, because all conclusive sentences in textbooks are printed in bold fonts. The students can tell at a glance where the answer to my question is. But my intention is not here. The next question is what I want to ask.

Five minutes later, a student raised his hand, and then he stood up and read the conclusion in the textbook: "The size of the image formed by a flat mirror is equal to the size of the object, the distance from the image to the flat mirror is equal, and the connection between the image and the object is perpendicular to the mirror."

After he finished reading it, I said, "Do you think this sentence about the imaging characteristics of the flat mirror he found is correct?"

"Yes," the students replied in unison.

The students who stood up were ready to sit down, and I immediately said, "Don't panic and sit down, I still have questions." This classmate was cheated by me, so my next question is not as simple as finding the answer in the textbook. )

I went on to say, "when describing the imaging characteristics of flat mirrors, this sentence in the textbook mainly tells the relationship between images and objects from two aspects." The first is the size relationship between the image and the object, and the second is the position relationship between the image and the object. The textbook says that the image is equal to the size of the object, and the distance from the image to the plane mirror is equal to the distance from the object to the plane mirror. "

After that, I asked the standing students, "Do you think the conclusion in the book you just read is correct? Do you believe it? "

The student looked at me with puzzled eyes (I know why the student looked at me with such eyes, because he thought so in his heart. The teacher's question is a bit idiotic. How can there be mistakes in the book? ), thought about it and said, "Yes."

Then I asked the class this question: "Do you think this conclusion written in the book is correct? Do you believe it? "

No one answered.

They were lost in thought.

At this time, I asked the classmate to sit down and said, "Don't think that everything written in the textbook is correct, and everything written is bold. There are many mistakes in this book. Textbooks are also written by people, but everyone makes mistakes. " What's more, you probably don't know that many wrong things in this world are spread by the words in books, and we don't have to believe what is written in books. Learning scientific knowledge is actually a process of questioning phenomena and authority, and the essence of scientific spirit is doubt. Every scientific progress of mankind begins with doubt. Today we will question this conclusion in the textbook. Now, please close your textbook and think about the following questions. We don't know whether what is written in the book is correct now. We can only assume that what is written in the book is correct. Now can you find a way to conclude that the image written on the certificate is equal to the size of the object and the distance from the object to the plane mirror? If you can prove it through experiments, we will believe the facts. "

I see many students thinking because they can't read textbooks. They can only think from their own life experiences. How can they prove it?

This is a hint that I have to do, otherwise the students have no concept at all and are thinking.

I went on to say, "according to my life experience, if I put a mirror in front of you now, you will see your beautiful face in the mirror." Is there any way to know for sure that your face in the mirror is as big as your own? "

Many students said smoothly, "As big as them, they look the same."

I said, "It's just your feeling to look the same size. When we used to learn to measure length, we all said that people felt unreliable. "

A student can't wait to say, "Teacher, you can measure the size with a scale."

The students are whispering to each other. They are discussing in a low voice.

I looked at all the people around me with my eyes and said, "Do you think a scale can accurately measure the size of a person's face? For example, how do you accurately measure the height of my nose, the thickness of my eyelids and the size of my ears with a scale? These are simply accurate. "

The students were lost in thought again. What should we do?

A classmate suddenly said, "Teacher, it is too difficult to measure a person's face with a scale, so change it to something easy to measure, such as putting a cube in front of a flat mirror or putting a blank sheet of paper in front of a flat mirror."

(I thought, "Well, use your head") Everyone thinks this method is good. But my next question stumped them. I went on to say, "Well, we don't measure people's faces now, we measure white paper, but the question is, when you measure the size of white paper, how do you measure the size of the image of white paper in the mirror?" When you turn to the back of a flat mirror to measure the image of white paper, can you touch it? The image of a flat mirror is not real at all, so you can only look at it but not touch it. For a fictional person,

Thinking is deadlocked again.

I went on to say, "The size of this image cannot be measured. How do we compare sizes? " Why can't we say that the image is equal to the size of the object against the book? "

I went on to say, "well, let's open our textbooks and see what is done in the books." The textbook mainly draws the conclusion of the imaging characteristics of flat mirror through an experiment. Now please read the experimental process of this experiment carefully and find out how to measure the size of the image in the book. "

I walked around the classroom and saw that the students who had just skimmed the preview were now seriously looking for how to solve this unmeasurable problem in the book. I think students must be very curious about what they cannot measure. How did they do it in the book? I spared such a big circle just to arouse students' curiosity and guide them to read textbooks carefully.

A student raised his hand: "I know, teacher, this experiment in the book doesn't measure the size of objects and images at all." Just use two candles with the same size, one lit and the other unlit, and put them on the left side of the glass plate, and then they will become an image on the right side of the glass plate, and then put an unlit candle at the position where the image is lit, as if it were lit. At this time, I saw that the unlit candle and the lit image completely coincided.

At this time, I saw that some students' doubts have been solved, and some students don't understand what this means.

In order to encourage this classmate, I suggest: "There should be applause at this time."

After the applause, I took out two identical candles prepared in advance (candles are not easy to buy now, so I went to several places to buy candles for this class, and the glass plate was borrowed from the glass shop) and began to do experiments. The students were immediately attracted by what I had in my hand, and the students behind me stood up to watch.

Then, in order to dispel the doubts of other students who don't understand the experimental principle, I compared the experimental equipment and described the experimental principle and steps.

At this point, everything is ready before the experiment. I use one question after another to mobilize students' thinking step by step. It can be said that I will enter the climax of this class next. Then, the conclusions in the book are drawn through experiments. At this time, students all think that what is written in the book is correct. At this time, knowledge becomes a part of students' cognitive structure. Because of this process, in this class, students don't passively listen to the teacher about how to do this experiment and what kind of conclusions are drawn, but think carefully before doing the experiment and drawing conclusions, be stumped by questions, and study textbooks with curiosity.

When I finished this class and reflected after class, I realized that a good class must not be a simple knowledge transfer, but an enlightenment of thinking. There was a time when people especially wanted an "efficient classroom". I heard a school leader say that "efficient class" is to improve the efficiency of class. Teachers can talk for no more than fifteen minutes, then let students do exercises, solve problems in class and achieve openness. Now that I think about it, I can't say that this leader is wrong, but at least it is superficial. I don't believe that any classroom model can be applied to any class like a master key, let alone stipulate how long the teacher will speak. All school leaders who rely on models to tell teachers how to teach are leaders who don't understand the laws of education and command blindly. Different subjects, different classes, different students, each teacher's style is different, how can we ask for a pattern in class? I think the so-called efficient classroom is not to improve the efficiency of class, but to inspire students' thinking and make them think. Students think about the difficulties of this class in class and turn them into a part of cognitive structure. This kind of classroom is efficient.

It's time for the students to finish this experiment. I arranged an assignment. I went home at the weekend to do the experiment of flat mirror imaging by myself, recorded the experimental video and sent it to the WeChat group of our class, so that everyone could learn from each other.

When I wrote this article, there were still students in the WeChat group posting videos, and it was already past ten o'clock in the evening. The following are some success stories I selected from the video for your reference:

Now it is increasingly felt that it is really not easy for teachers to do this job well. In order to have a good class, the time for preparing lessons and reflecting after class occupies several times or even ten times of the class time. From finding experimental equipment to sorting out after-class records and reflections, to sorting out and editing students' experimental videos, I have almost no weekends to spare. Many laymen always say, "A teacher's job is easy. They have two classes a day, winter and summer vacations, and rest for several months a year. " What I want to say is that laymen don't understand it at all and are too lazy to explain it to them.