20 years of teaching

Chapter 483 Who Is The Third Person
During the preliminary round, the five judging groups lived in five different classrooms on the fourth floor.

A reception room is set up on the third floor, where the lottery is completed. Players can wait for the competition here, and they can also come here to drink tea and chat after the competition.

First draw the serial number, then take out a ball of paper from a glass container, and take a look at it, Lin Feifei couldn't help but feel a little disappointed.

A capital "Lu" was written on the paper, that is, the sixth group. Each group can arrange five contestants to attend the class, and the sixth group is the last group.

It has been indicated on the competition schedule that there will be three groups in the morning and three groups in the afternoon, and the sixth group will not start class until 03:30 in the afternoon.

The teachers who got the fourth, fifth, and sixth groups all left the reception room one after another, some yelled and went shopping in the street, and some whispered that they would go back to the hotel to play cards.

The organizing committee arranged hotels for all contestants and teachers who participated in the senior high school entrance examination seminar.

Everyone basically arrived yesterday afternoon and lived in the same hotel. There were two people in each room. The teachers who participated in the competition sat at three adjacent tables during the meal. Basically, they were already familiar with each other.

This kind of special review class is still an original test question, unlike a new class, you can't start to prepare in advance.

Then, why don't you prepare any more, take a trip to the provincial capital after a long time, and take this opportunity to have fun and relax.

However, Lin Feifan did not leave. Instead, he sat in the reception room and waited patiently, helping the teachers to carry bags, teacups, mobile phones and other things. After others came back from class, he asked for review topics in time.

After the class, this topic became a piece of waste paper. Everyone was very generous and gave Lin Feifan a special topic. They also kindly said that everyone’s topic is different. Spending time on the topic that has already been completed is of no use. big.

However, every time Lin Feifei got a project, he looked eager and eager to calculate it on the draft paper.

Some topics are not difficult and relatively simple, while some topics are indeed very novel, with unique design ideas and relatively high difficulty.

After each teacher returned to the reception room, he had to discuss with Lin Feifan.

Among the 25 teachers in the first five groups, 7 teachers came down after staying on the fourth floor for more than ten minutes.

Sadly, within 10 minutes of preparation time, I couldn't find an idea for the selected competition topic.

The teacher didn't even figure it out, so how can he tell the students?

Talk about a fart!

So I had to be a deserter and temporarily abstained.

During the discussion with Lin Feifan, four teachers discovered that they had made a mistake...

Teacher Jia, who slept in the same room as Lin Feifei, said: "Damn it! No wonder some judges curled their lips and shook their heads during class, and some students covered their mouths and snickered. Reminder? Don’t all students know how to do it?”

Lin Feifan said: "Probably, maybe, er, definitely. The review team made requirements for the students. If the teacher made a mistake, the students should not remind the teacher. The middle school affiliated to Jianghuai Normal University has masters like Lin, and every year the national junior There are many students here in the first prize list of the high school Olympic competition. It is impossible for them to solve this kind of problem.”

How embarrassing to spend the whole class talking about the wrong things and spitting and laughing at yourself!

Teacher Jia covered her face and let out a long sigh, "I'm ashamed! I really want to find a crack in the ground!"

Lin Feifan comforted and said: "It's okay, you are not the only one who is wrong, and some teachers, although the main direction is correct, there are more or less problems."

Indeed, Lin Feifei counted 25 people, seven of whom gave up the class because they couldn’t do the questions, four of them made mistakes, and the lectures were in vain, and there were still four people’s deficiencies in the narration process. Ideas, skills, calculations, etc. are debatable.

In other words, among the top 25 people, [-] people did not succeed in this competition class, so they should have been eliminated in advance and missed the award.

Finally it was the sixth group's turn. Lin Feifan and the other four went to the fourth floor and walked into different classrooms.

The judges and students are already in place. The judge in this classroom is Ge Jun as the team leader. He holds a stack of folded white papers and asks Lin Feifan to choose one of them.

Lin Feifan took the top one and opened it, feeling a little disappointed.

[Assuming that there are two sounds coming to the human ear, if the time interval between the two sounds reaching the human ear is greater than (or equal to) 0.1S, the human ear can distinguish the two sounds, that is to say , if the time interval between the two sounds reaching the human ear is not enough, the human ear can only hear the sound once.In order to experience the physical phenomenon that the propagation speed of sound is different in different media, the extracurricular activity group of the second grade of Qingbei Middle School asked a student to tap on the water pipe (full of water) to make the iron pipe make a crisp sound , and the rest of the students put their ears close to the iron pipe at different positions along the iron pipe to listen to the sound.After the experiment, student A said that he only heard the sound once; student B said that he heard the sound twice; student C said that he heard the sound three times.It is known that the propagation speed of sound in the air is 340m/s, the propagation speed in water is 1500m/s, and the propagation speed in steel is 5200m/s, please explain through calculation: knock once somewhere on the iron pipe , What is the distance between the positions of the three students and the tapping point? (Write out the calculation process and the analysis process of the conclusion)]

Doesn't it mean that every subject is difficult?
Why is this question so simple?
Some time ago, Li Minyao asked a question, which was similar to this one, but much more complicated.

"Can we start?" Lin Feifan asked.

All six judges were stunned.

Ge Jun reminded: "You have 10 minutes to prepare."

Lin Feifan smiled and said: "There is no need to prepare, so that there are so many people waiting, we can start now."

Ge Jun looked back, and the service staff hadn't finished distributing the questions to the students, so he said, "Wait another two minutes, after all the students get the test papers, you can start."

In the meeting in the morning, I said that each question is very long, and the participating teachers do not need to copy the questions on the blackboard. The organizing committee will print dozens of copies of each question, and each student will have a copy.

After each student got the topic, Lin Feifei shouted: "Let's go to class."

"Stand up!" the squad leader's voice.

"Hello teacher!" The voice was neat and loud.

Lin Feifei smiled and nodded, "Hello, students! Please sit down."

Even if it is a high-quality class competition, as long as there are students participating, there is still a sense of ceremony.

Next, Lin Feifan guided the students to solve this problem in an orderly manner, just as he usually did in Jinghu Middle School.

[-]. Read the question again, lead the students to review the question carefully, and emphasize some key points.

Second, let the students think independently for 5 minutes, and try to find a way to solve the problem.

8. Exchange and discuss for [-] minutes. The students who can’t do it will ask the students who can do it. The students who can do it will explain carefully, and try to let the students who can’t do it know how to solve this problem.

Within the scope of the classroom, you can discuss with any classmate.

It doesn't matter if you walk around the classroom to discuss topics, you can run wherever you like.

Of course, you can also discuss with the teacher.

Or maybe it was because the children in this class seldom experienced such discussion sessions when they were taking new classes. The children suddenly became excited, hula-la forming several circles, discussing enthusiastically.

A few of the bold students surrounded Lin Feifei, asking if they could answer this question in one way or another...

The six judges were also discussing together. They were not discussing this topic, but discussing this kind of teaching method that they had never seen before.

[-]. Ask eight students to go to the blackboard, four students on the front blackboard, and four students on the back blackboard, to answer this question in a standardized manner on the blackboard.Other students wrote the calculation and analysis process of this topic on the draft paper.

If you are familiar with the students, in the fourth link, students who can basically answer this question should be selected to go to the blackboard to play a demonstration role.

However, the following students do not know any of them, and do not know the details of their grades.

In a class, there are some students with excellent grades, some with poor grades, and children with very poor grades. Even if they seriously discuss with others, they still cannot grasp the thinking of solving problems.

In order to face all students, this link does not determine which students go to the blackboard by raising their hands.

Instead, in four groups, each group randomly selected two students to go to the blackboard.

It is very likely that students with very poor grades will be called. After going to the blackboard, they will not be able to write a word.

Lin Feifan made some adjustments in this session, and kindly reminded that if any of the eight students on the blackboard could not solve this test question, he could ask a friend to help him solve this question together.

Sure enough, there were two students who couldn't start with the topic and couldn't write a word on the blackboard.

Lin Feifan once again emphasized that he could ask for help.

It is very interesting that the female class leader who shouted "stand up" stood up immediately, pulled her deskmate together, and took the initiative to go to the blackboard to help two students who couldn't do the questions to answer the test questions, explaining while writing...

Taking advantage of this time, Lin Feifei walked back and forth in the classroom to see how the students were answering, and gave a classmate some pointers from time to time.

……

After a cursory review of all the students' answers to the questions, Lin Feifei lamented that these children are worthy of being the students of the High School Affiliated to Jianghuai Normal University. Most of the students can answer the test questions very well, and the answering process is very standardized, with neat and beautiful handwriting.

Only by teaching students in accordance with their aptitude can we obtain the greatest results!Lin Feifan decided to speed up the teaching progress in order to try to teach students more things in this class.

[-]. By raising their hands, ask eight students to go to the blackboard to correct the test questions with red pens.The other students exchanged the test questions back and forth, left and right, and approved each other.

According to past experience, those who dare to raise their hands on the blackboard to make corrections are all students with excellent grades. The higher the hand is raised, the more confident they are, and they must have found something wrong on the blackboard.

……

Looking at the results of corrections on the blackboard, Lin Feifei nodded and smiled frequently. All the small mistakes he found were discovered by the students who corrected on the blackboard...

While the students were still discussing right and wrong, the six judges gathered together to discuss in a low voice. They were still not discussing the topic, but were they discussing whether this counts as a teacher's class?

In one class, there is not much time left. The teacher didn't seem to do anything other than spend two or three minutes reading the questions carefully.

Sixth, it was finally Mr. Lin's turn to play. First, he praised the advantages of all the students one by one, and then summarized the problem-solving methods, ideas and skills of this type of questions, emphasizing the importance and steps of standard problem-solving .

Because the children's grades are generally better, the teaching progress has been accelerated, and there is still some time before get out of class ends.

Lin Feifan threw out the question that Li Minyao asked that was much more complicated than this question, and wrote down the key data, known conditions and required quantity on the blackboard.

Then it is required to combine the problem-solving experience of the previous problem to tell the problem-solving ideas of this problem.

After being reminded by Lin Feifei, two students soon raised their hands, and one of them was the class monitor.

The other one is a boy.

Looking at the clock hanging on the wall behind the classroom, there are still 6 minutes to finish class.

The student who found the solution to the problem so quickly must be a master, and should be able to solve the problem in the remaining time.

Lin Feifan smiled and said, "Now three people will go to the blackboard to answer this question, let's see who can do it first! The other students will finish it on scratch paper."

Only two classmates raised their hands, who is the third person?
The two students who raised their hands began to write the solution process on the blackboard.

Lin Feifan picked up the chalk and started to do the questions in a side area.

All of a sudden, the whole classroom boiled.

Ha ha!The squad leader, the study committee member, and the teacher are competing.

Lin Feifan intentionally slowed down and waited for the two students to put down the chalk before writing the final answer.

The three people gave exactly the same answer.

"I lost!" Lin Feifei laughed.

Hahaha——~~

Everyone laughed happily, very happy.

The squad leader stood up and waved his hands, motioning everyone to be quiet, and said loudly: "The teacher is showing us the standardized answering process."

The study committee member said: "The teacher's answering process is much more rigorous than the two of us, students quickly copy it down."

Lin Feifei smiled and nodded his thanks: "Thank you for your tacit cooperation! get out of class is over!"

"stand up!"

"goodbye teacher!"

……

……

(End of this chapter)