Simple and interesting little knowledge in class

1. A short knowledge of mathematics is about 20 to 50 words.

Interesting knowledge of mathematics

Number theory part:

1, there is no maximum prime number. Euclid gave a beautiful and simple proof.

2. Goldbach conjecture: Any even number can be expressed as the sum of two prime numbers. Chen Jingrun's achievement is that any even number can be expressed as the sum of the products of one prime number and no more than two prime numbers.

3. Fermat's last theorem: n power of x+n power of y = n power of z, and n> has no integer solution at 2 places. Euler proofs 3 and 4, 1995 were proved by British mathematician andrew wiles.

Topology part:

1. The relationship among points, faces and edges of a polyhedron: fixed point+number of faces = number of edges +2, which was proposed by Descartes and proved by Euler, also known as euler theorem.

2. euler theorem's inference: There may be only five regular polyhedrons, namely regular tetrahedron, regular octahedron, regular hexahedron, regular icosahedron and regular dodecahedron.

3. Turn the space upside down, the left-handed object can be changed into the right-handed, and through Klein bottle simulation, a good mental gymnastics,

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2. Primary education: simple and interesting scientific experiments.

Paid newspaper

Thinking: Without glue, tape and other things, newspapers can stick to the wall without falling off. Do you know why?

Material: 1 pencil; 1 newspaper.

Steps:

1. Spread the newspaper and lay it flat on the wall.

2. After a few quick rubs on the newspaper with one side of the pencil, the newspaper won't fall off just like sticking to the wall.

3. Lift a corner of the newspaper, and then let go, and the lifted corner will be sucked back by the wall.

Take the newspaper off the wall slowly and pay attention to the static sound.

Description:

1. Wipe the pencil to charge the newspaper.

2. The charged newspaper was sucked to the wall.

When the indoor air is dry (especially in winter), if you take down the newspaper from the wall, you will hear the crackle of static electricity.

Creation: Please have a try. What else can be stuck to the wall by static electricity without glue?

Separation of pepper and salt

Thinking: I accidentally mixed the kitchen condiments: pepper and salt. How can I separate them?

Ingredients: pepper, salt, plastic spoon, small dish.

Operation:

1. Mix salt and pepper.

2. Stir well with chopsticks.

3. Rub the plastic spoon on the clothes and put it on the salt and pepper.

4. Pepper sticks to the spoon first.

5. Move the plastic spoon down slightly.

6. After salt, stick it on the spoon.

Explanation:

Pepper is electrostatically adsorbed earlier than salt because its weight is lighter than salt.

Create:

Can you separate other mixed materials in this way?

Inflatable balloon

Thinking: When will two balloons attract each other and repel each other?

Material: 2 inflatable balloons, 1 string, 1 cardboard.

Operation:

1 Inflate two balloons separately and tie a knot in your mouth.

Connect two balloons with a thread.

Rub the balloon on your hair (or sweater).

Lift the middle part of the rope and the two balloons will separate immediately.

Put the cardboard between two balloons, and the electricity on the balloons makes them attracted to the cardboard.

Explanation:

The electricity on one balloon repels the electricity on the other balloon.

The electricity on the two balloons attracts them to the cardboard.

Creation: Can other small experiments be used to illustrate that balloons are charged?

Lovely watermark

Thinking: The beautiful patterns on rice paper are not drawn, but how are they made?

Materials: 1 washbasin, 1-2 rice paper, 1 chopsticks, 1 cotton swab, 1 bottle of ink and water (about half a basin).

Operation:

1. Pour half a basin of water into the washbasin and gently touch the water surface with chopsticks dipped in ink. You can see that the ink expands into a circle on the water surface.

2. Wipe the scalp with a cotton swab for two or three times.

3. Then touch the center of the ink circle and see what happens.

4. Gently cover the calligraphy paper on the water, and then pick it up slowly. What patterns are printed on the paper?

Explanation:

1. When the cotton swab touches, the ink will swell into an irregular circular pattern.

2. A small amount of oil on the scalp rubbed by cotton swabs will affect the mutual pulling force of water molecules.

3. The watermark will present irregular concentric circles.

Create:

Try other methods to change the ink pattern on the water surface.

3. What simple and interesting experiments can be done in the science common sense class in primary schools?

The dispersion of physical light, such as rainbow, introduces knowledge! Explain that white light is not monochromatic light! 2. Concave-convex lenses, use concave lenses and myopia magnifying glasses to learn lens knowledge among students, but enough is enough! With regard to gravity, we can use the story of Newton and Apple to illustrate that objects are attracted by gravity, and further illustrate that this force that makes physics fall is gravity. 4. Siphon phenomenon is explained by the common sense of changing water in fish tanks! 5. Principle of communication device, 6. The magic of atmospheric pressure: why does water flow from the bottom to the mouth and throw it out with a straw, which further explains atmospheric pressure? 7. Crown Crane: Generally, there are flagpoles at the top of flagpoles in primary schools, and then ask the function of crown crane. 8. Light travels in a straight line: solar and lunar eclipses are used to introduce problems.

4. What simple and interesting experiments can be done in the science common sense class in primary schools?

Physics class

1. The dispersion of light, such as rainbow, introduces knowledge! Explain that white light is not monochromatic light!

2.2. Concave-convex lenses, students learn lens knowledge with concave lenses and myopia magnifying glasses, but enough is enough!

With regard to gravity, we can use the story of Newton and Apple to illustrate that objects are attracted by gravity, and further illustrate that this force that makes physics fall is gravity.

4.4. Siphon phenomenon is explained by the common sense of changing water in fish tanks!

5.5. The principle of communication device,

6.6. The magic of atmospheric pressure: Why does water flow from the lower part to the mouth and throw it out with a straw to absorb water, which further explains atmospheric pressure.

7.7. Crown block: Generally, primary schools have flagpoles, and there is a crown block at the top of the flagpoles. Then ask the crane about his role.

8.8. Walk in a straight line: use the solar eclipse to introduce problems!

5. Q: How can we make the class more interesting?

Many teachers complain that students don't like learning and have poor classroom discipline. In fact, children's nature is to love to play, so it is really hard for them to be confined in such a small space in the classroom and accept some boring knowledge. As their teachers, what they can do is to make the class as lively and interesting as possible and let the children be baptized by knowledge in a more pleasant environment.

Methods/steps

Exchange teacher-student relationship

Changing the traditional teaching mode in which teachers speak on the stage and students listen below, so that students can become the main body and give lectures or do problems on the platform, can effectively stimulate students' enthusiasm for autonomous learning, thus making the classroom more dynamic.

Education through entertainment; to educate through entertainment; combine education and entertainment

Enriching the teaching language and telling knowledge in the form of interesting stories are the easiest ways to attract students' attention and enliven the classroom atmosphere.

experiment

As it turns out, students like to watch the teacher fiddle with a new thing on the podium. Therefore, in class, teachers should not only use books, chalk and pointers, but also use some intuitive teaching AIDS to do a classic experiment, which is the best way to make the class lively.

Humorous

Teacher Yi Zhongtian spread all over China, causing a small wind in the Three Kingdoms. The reason is not only his profound knowledge, but also a little humor with wisdom that comes out from time to time. Teachers with humorous lecture style can not only make students feel their own shining personality charm, but also make the whole process of listening to a lecture like listening to a paragraph.

Multiple interaction

In class, teachers should not speak by themselves blindly, but should interact with students in various ways. For example, ask a few small questions and let the students sitting on the diagonal of the classroom answer them. For example, students can perform small dialogues in English class. For junior students, you can also reward small red flowers to make the class more lively and interesting.

A brief episode

Interspersing some content unrelated to the course during the lecture sometimes has unexpected effects. Some courses are boring and hypnotic, and it is difficult to remedy them by the above means. It is wise to tell a joke or play an interesting video when students are on the verge of collapse, which can enhance the interesting value of the whole class.

6. What is the easiest and fun way to learn?

1. Preview: After previewing the whole content of the textbook, read it carefully, give full play to the self-study ability, sort out what you already know and what you have doubts or don't understand (that is, find the key points and difficulties), mark it and write it down.

This not only improves the ability of self-study, but also paves the way for attending classes, forming a psychological set that expects teachers to analyze; This set of psychological needs will definitely stimulate our enthusiasm for learning and highly concentrated attention.

Second, attending classes: Listening to the teacher is the best shortcut to acquire knowledge, and the teacher teaches the truth that has been verified by history; It is the essence of teachers' long-term study and teaching practice. It is particularly important to improve classroom efficiency;

1, get ready before class: mental preparation is very important. Keeping energetic and clear-headed in class is the premise of learning knowledge well.

2. Concentrate: If you are distracted, you should concentrate on listening and eliminate interference.

3, careful observation, positive thinking: don't be a passive receiver of information, to fully mobilize their enthusiasm, listen to the teacher's teaching ideas, will achieve good learning results.

4. Fully understand and master the methods.

5. Grasp the key points of the teacher's lecture: Some students often ignore the beginning and end of the teacher's lecture when listening to the class, and at the same time pay attention to the parts repeatedly emphasized by the teacher.

Taking notes in class is one of the best ways to strengthen memory. Notes, an eternal record, can overcome the limitations of brain memory. As the saying goes, a good memory is not as good as a bad writing, so you must take notes. At the same time, taking notes and fully mobilizing the cooperation of ears, eyes, hands and heart are helpful to learning.

In short, it is a process of accumulation. The more you know, the better you will learn, so remember more and choose the learning method that suits you. I wish you success in your study!