1. Read the text correctly, fluently and clearly. Learn about Mars, know about Mars, and explore the unsolved mystery of Mars through online self-study.
2, can feel the accuracy of scientific explanation.
3. In inquiry learning, learn to browse, organize and process information, expand the understanding of the background content of the text, and enhance your information literacy and language organization and expression ability.
4. With the help of the specific language materials in the text and the relevant materials provided on the special study website, stimulate students' feelings of loving science and being willing to explore the mysteries of the universe.
Emphasis and difficulty in teaching:
1 Read the text with emotion
Understand the content of the text and why people call the earth and Mars the solar system. Twin brothers? To understand the similarities and differences between the two.
Teaching preparation:
courseware
Teaching process:
first kind
First, create situations and introduce new lessons.
1, students, a long time ago, about 5 billion years ago, there was an accident in the Milky Way. After its core temperature rose sharply, a nebula burned into a yellow star (guess who this is? ) This is our sun. A large number of cosmic dust particles revolving around the sun gradually gather into a group, forming nine planets, two of which are very close. They look so different, but they have many similarities.
2. The earth is the home of our human life, but human beings have been longing for a new home and looking forward to the emergence of new life. To this end, scientists have made unremitting exploration of the universe and finally discovered this planet (Mars) which is very similar to the earth's ecology.
Mars is so mysterious! Let's get close to our neighbors first.
Today, we will learn an article about Mars. It can uncover some mysteries in our hearts.
(Knock out the topic) Who will read the topic aloud? Read together
Do you have any questions after reading the topic? (Why use double quotation marks? What do dashes do? )
3. Have you seen it? Twin brothers? Really? What do they look like? (It looks very similar. )
Second, explore exchanges and build independently.
( 1)
1, which pair is Mars and the Earth? Twin brothers? Where exactly does it look like? (Show the first paragraph) See for yourself. Where are they looking? (Students say, display: the same even number)
Can you use your reading to let us hear the similarities between them at once?
Try to read it yourself. Read by name.
(Comment: Just heard it? There are the same ones. Do you have the same? I didn't catch what was in it. What? That's all that matters. )
Read it again by name.
(Comment: I can see clearly, and I can hear clearly. )
Don't you think it's amazing Read this magic. Who will read it again?
Ok, read it together.
Students, you see, in this passage, four are used in succession? Same? , what is this called? Do you know that?/You know what? (parallel). What do you see from this set of parallelism? (very similar)
In fact, their similarities are more than that. Please read the first paragraph and see what similarities they have.
You will read about them, too. What else is similar? Read it aloud.
What did you browse? What similarities did you find?
L (eyes looking ahead) Yes, look, these two brothers are really alike. Besides so much in common, let's have a set of parallelism sentences to tell us the similarities you read.
Not only that, they almost, almost, almost,
Even.
No wonder (introduction) people call the earth and Mars the solar system? Twin brothers? And it is speculated that Mars also has water and life like the earth.
(2)
With the deepening of exploration, scientists really found that the two brothers have one thing in common except their looks. Please enjoy reading paragraph 25 in middle school. Read aloud and find out which sentences tell you that the two brothers have something in common. First of all (the source of water), please read the sentences you find out aloud.
From which of these two sentences do you see that they have something in common? Read it again and let us understand. From these two sentences, we know that their similarity is the source of water.
4. How did the water on Mars and the earth come from? Read 2-5 paragraphs by yourself. When reading this time, you can open the text, browse the relevant materials to help you understand, and then try to explain the origin of water in your own language.
While browsing, discuss at the same table.
Name theory
Not concise enough. Can you read the hint and say it briefly? Talk to each other at the same table.
(Show: Meteor comet (containing water) collides with volcanic eruption.
Mineral (water-bearing) steam, rain lake, ocean)
Roll call (evaluation: reading should be good at grasping key words and extracting important information. )
L 5, but the text seems to be different from what you said! The text goes like this:
(Show: Perhaps comets and meteorite storms that lasted for hundreds of millions of years brought the first water to the brothers.
Like the earth, there may be another water source on Mars. Boys read this sentence and girls read the second sentence.
Why do you say that? This is science, and its words must be accurate and rigorous. Without sufficient evidence, it is impossible to express it in definite language. And this process is just a guess made by scientists based on existing data. )
6. There is also a word inference in the article. Let's look at these two sentences.
) No wonder people call the Earth and Mars the solar system? Twin brothers? And it is speculated that Mars also has water and life like the earth.
2. Scientists studied and analyzed the photos of Mars, and found that there is a dry river bed on Mars, which is hundreds of kilometers wide, far better than the Amazon River on earth today. After March 2004, the inference that there is water on Mars was further confirmed by drilling and analyzing the rocks on Mars. )
Read these two paragraphs and think about what these two words mean respectively.
(guess: imagine according to the facts. What is imagined here? Mars has many similarities with the earth, so it is thought that Mars may have water and life like the earth.
Inference: draw a conclusion based on facts. Read this passage again. What's the conclusion here? According to the analysis of dry river bed and rock drilling, it is inferred and concluded that there was water on the earth. )
If these two words were exchanged, would you?
Let's look at such a context:
reason
On the basis of analyzing the surface of Mars valley, Dr. Coleman made the following conclusion: Mars was a water world a long time ago, but it was not necessarily warm.
There used to be a lot of water on Mars, so scientists think there may be life on Mars.
7. Science is the most rigorous, as the scientist Zhu Kezhen said. Can't be used for research? Probably? 、? Maybe? Something like that. ?
It is with scientific evidence such as photos and data analysis that scientists can move from speculation to inference.
Third, summarize and expand.
1, let's take a look at these pictures from Mars. Looking at them, you seem to have seen and heard what happened more than 4 billion years ago. (Imagine speaking) It seems to be in front of my eyes and in my ears.
Through today's research, we can see that in the process of creating life, Mars and the earth were originally on the same starting line. They were born almost at the same time, and both of them have water resources that can breed life, so people call them (repetition topics). Let's look at the topic again. Look at the topic together.
Now, can you tell me? Twin brothers? Why use quotation marks? (indicating a special meaning. )
What do you think of this metaphor to describe the relationship between the earth and Mars? (Very humorous, vivid and vivid) The figurative metaphor makes the originally boring popular science paper vivid, interesting and easy to understand.
What does the dash in the title mean? (indicate explanation)
But later, the fate of the two brothers was completely opposite. Our earth is full of life because of water, but Mars is barren and dead.
At this time, you must have a lot of doubts about Mars. Students, at this time, put all kinds of interesting topics or questions in your mind? Mars forum? On the table, we will explore together.
L Provide students with feedback, free speech, and space to continue discussion after class.
Step 3 communicate
Students, Mars has many mysteries worth exploring. Students can fully browse the information in the learning website after class, and also use their own search engines to explore the vast online world. We will continue to learn communication next class.
blackboard-writing design
6 Mars-Earth? Twin brothers?
The similarities are the same.
water
The difference is that water can't stay.
Life survival? (mysterious)
Second lesson
First, introduce and reveal the theme.
1, lead: the dream is flying around, which makes us excited. We humans have taken a small step to explore the universe. In the starry sky, we know that Mars and the earth are "twin brothers", so why do scientists call Mars and the earth twin brothers? Since they are twin brothers, what are their similarities and differences? (Blackboard: Similarities and Differences) Today we will continue to study and discuss this problem.
2. Students read the questions together. Please open your textbook.
Second, review and review
1 Read the first paragraph
What do you mean? Speculation? Imagine what you don't know from what you already know. )
Scientists speculate? Mars also has water and life like the earth? What is their basis?
Students read (? Same, same, same, even? )
Four? Same? And then what? Even? The fabricated parallelism shows that Mars is very similar to the Earth.
It seems appropriate to call the Earth and Mars "twin brothers" in the solar system. Very vivid. No wonder people call the Earth and Mars "twins" of the solar system? Twin brothers? .
2 Read and understand the second paragraph (paragraphs 2 to 5)
1, scientists call Mars and the Earth twin brothers. We know that they are very similar, but now there are vast oceans and colorful life on the Earth, so is there really water and life on the little brother Mars? Read the second paragraph by name and underline the relevant sentences:
( 1)? Inference? What do you mean?
Health: guess, sum up
Teacher: What conclusions did the scientists draw?
Health: There used to be water on Mars. [Blackboard: There used to be water]
(2) On what basis do scientists infer that there is water on Mars?
(3) Students read independently and discuss and summarize at the same table. Intention: to stimulate students' strong thirst for knowledge and cultivate their general expression ability.
There are two reasons: first, by analyzing the photo data of Mars, it is found that there is a dry river bed on Mars, which is hundreds of kilometers wide; Secondly, through the drilling analysis of Martian rocks, it is confirmed that there was water on Mars.
2, contrast, multimedia presentation:
A, scientists studied and analyzed the photo data of Mars, and found the dry river bed, which is hundreds of kilometers wide, far better than the Amazon River on earth today. After March 2004, the inference that there is water on Mars was further confirmed by drilling and analyzing the rocks on Mars. So where did the water on Mars come from?
(1) See for yourself. This is a sentence that analyzes the text and concludes that there was water on Mars. Explanatory text requires concise language, just make things clear. The following is a sentence changed by the teacher, which also explains the same thing. Please read and compare. The second paragraph is more concise. Can you change the original text into the second paragraph? Why? Show:
B, scientists found a dry river bed on Mars. After March 2004, mankind further confirmed the inference that there is water on Mars. So where did the water on Mars come from?
(2) Group communication, learn from each other's strong points, and further enrich their views.
(3) Guide communication, the teacher comments in time, and let the students know that the following sentences or words can't be omitted, and the students will point to one place when they talk about it.
? Scientists studied and analyzed photos of Mars? Scientific research and scientific speculation cannot be fabricated out of thin air, but must have certain scientific basis. (Click on the picture of Mars river bed in the multimedia courseware at the same time)
? The riverbed is hundreds of kilometers wide, far better than the Amazon River on earth today? Compared with the familiar things on earth, it is easier for people to feel the scale of the dry river bed on Mars. Is this common in expository writing? List numbers? , ? Compare? Method.
? Analysis of Martian rocks by drilling? It shows that the confirmation of scientific inference should also pay attention to evidence. This is a scientific research attitude. (Show drilling drawings and supplement written materials)
? Once? The word implies that there is no water on Mars today. Only in the distant past did there be water on this planet. This statement is more scientific.
(4) Read the second paragraph all the time.
So, where did the water on Mars come from? Read the third to fifth paragraphs by yourself and draw the relevant concluding sentences. (Students study independently and then communicate)
Conclusion of multimedia presentation:
First, comets and meteorite storms that lasted for hundreds of millions of years sent the initial water to Mars;
Second, at the beginning of the birth of Mars, the composition of water has been hidden in some minerals.
4. Students carefully read the third to fifth paragraphs of the text with questions to understand the source of water on Mars.
How do comets and meteorites send water to Mars? (Combined with watching videos of comets hitting Mars and Earth)
(2) How did the water hidden in minerals come to the surface of Mars?
5.( 1) Discuss the first question, interspersed with discussion: Contact the context and talk about your understanding of adding words in the following sentences.
At that time, there were countless large and small fragments wandering around in the solar system, and it was common for them to collide with each other.
Routine: The original meaning refers to the common and frequent occurrence. This paper points out that countless large and small fragments in the solar system wander around and collide with each other, which may happen at any time and place and is very common.
What other words in this paragraph express the same meaning? (? Often, suddenly, countless, everywhere? )
(2) Discuss the second question (combined with animation demonstration)
6. Why did the author use the words "possible" and "possible" when describing the source of water?
Students think and communicate: because this is a scientist's guess, it may not be completely accurate.
7. Oral Practice: (Combined with pictures) Please try to tell where the water on Mars comes from. You can't make scientific mistakes when you say it. Pay attention to the conciseness of language and scientific rigor. Give it a try!
8. Students prepare, then let two students say, and the teacher leads the other students to comment together.
9. Look at the second paragraph together. Summary: Some scientists speculate that there are two sources of water on Mars: one is brought by meteorites or comets, and the other is hidden in some minerals.
[blackboard writing: the source of water]
3. Read the third paragraph (paragraphs 6 to 8) carefully.
1, look at the sixth paragraph and talk about the role of this paragraph in the text (transition, causing the following)
2. Read paragraph 7 carefully and discuss: Why is there no water on Mars?
(1) Guide students to discover and show the fatal defects of Mars itself and the resulting results.
(2) What are the fatal defects of Mars itself? Draw a straight line
How did these defects lead to this result? Draw it with a curve
(3) Multimedia show this passage and show the answer.
[blackboard writing: there is no water left]
(4) Understand the following sentences in the context.
A. Multimedia demonstration: The continuous escape of Mars gas makes it difficult for liquid water on the surface of Mars to exist for a long time.
B, guide understanding? Continuous? the meaning of
C, is it? Collective escape? What kind of scene is it? Guide the students to imagine that the liquid water on the surface of Mars evaporates into a large amount of gas and leaves Mars because of the small gravity of Mars.
D. Teacher's summary: The vivid language description method is used here, which makes the boring popular science books full of interest.
(5) Read aloud by name and read together.
3. Read the eighth paragraph by name and discuss: What does the eighth paragraph say? Is there life on Mars still a mystery? Dim? What do you mean? Water is the source of life. Since there is no water on Mars, why not say that there is no life on Mars? Scientists also say that there is little hope of finding life on the surface of Mars?
[blackboard writing: the mystery of life]
4. If there is life under the surface of Mars, what are they like and how do they survive?
Summary: The mysteries of the universe are endless, waiting for human beings to explore. Perhaps, after twenty or thirty years, you will be able to uncover one of them for mankind.
Fourth, read the full text and summarize the structure of the article.
1. Does the text revolve around Mars and the Earth? Twin brothers? How does this center arrange material narration? Why are the Earth and Mars called? twin brothers
Infer that there is water on Mars, and infer two sources of water.
Guess why Mars failed to retain water, and guess that there is life on Mars.
Verb (abbreviation of verb) summary and expansion
1, summary. Through today's study, we can see that in the process of creating life, Mars and the earth brothers were originally at the same starting line, they were born almost at the same time, and both of them have water resources that can breed life, so people call them (rereading the topic), but later their fate is completely opposite. Our earth is full of life because of water, but Mars is barren and dead. Why can't the water on Mars stay? I believe you must have a lot of doubts in your heart, which requires everyone to have scientific literacy from an early age, and then slowly study and discover.
2. Expand and extend
Read extracurricular popular science books
blackboard-writing design
"Twin Brothers" of Mars and Earth
Similar, the same difference, there is no water
There was once a mysterious aquatic creature.
The source of water