Chinese textbooks have completely solved the problem of seeing the weather from the clouds in Class 1 17, Grade 7.

Teaching Design of birds of paradise I

Small language forum users: black coffee

Release date: September 7, 2004 at 3: 53 a.m.

Teaching objectives

1. Learn the new words "leisure" and "homesickness" to show that the trembling South China is overwhelmed.

2. Train students to segment the text according to the author's tour order and summarize the meaning of the paragraphs.

3. Guide students to understand where things are static and where things are dynamic, so as to cultivate students' observation ability and writing ability.

Teaching focus

1. Understand the appearance characteristics of the big banyan tree and understand the meaning of "birds of paradise".

2. Learn the static and dynamic methods to describe things.

Class arrangement

Three classes.

Student activity design

1. Answer the questions designed in the article and tick the key words.

2. Discuss in situ, communicate in groups and understand key sentences.

3. Observe the pictures on the slide, use your imagination and train your language skills.

4. It is difficult to question.

Teaching step

first kind

Clear goal

1. Check the preview and ask questions.

2. Read the text for the first time and feel the main content of the article as a whole.

3. Clarify the levels, segment and summarize the meaning of the paragraphs.

(B) the overall perception

I have been to "birds of paradise" several times, what scenery have I seen?

(3) Process

1. Check the preview, ask questions and ask difficult questions.

(1) refers to reading the text, correcting pronunciation and explaining words.

(1) Pronunciation:

Trembling, overwhelmed, reading "A Cluster" in "yìng", "c" gap "and" x "

② Understanding words:

Nostalgia: Reluctant to give up, reluctant to leave.

I can't help it.

Display: To display clearly.

Southland: refers to the south of China.

Trembling: This lesson refers to the way leaves flicker when the breeze blows.

At a loss: The lesson is that the author can't see with his eyes because there are too many birds.

(2) Use "_ _ _ _ _" to underline the words you think are beautifully written in the text for reading and appreciation.

(3) Read the text freely and ask questions.

2. Expose the topic, student since the enlightenment:

(1) blackboard writing project.

What does "heaven" mean? How to understand it in the text?

What does "bird's paradise" in the article mean?

(2) Thinking about reading the whole text silently:

How many times has the author been to "Bird Paradise"? What's different every time I see it?

(The author has been to "Bird's Paradise" twice. The first time was in the yellow bird habitat. Therefore, the author focuses on describing the "heaven" itself-the strange sight of the big banyan tree; The second time, the next morning, when the sun just rose, it was the most active moment for birds, so I focused my eyes on the lively activities of the residents of "Paradise". )

3. Panel discussion:

We divided the author's two visits to "Bird Paradise" into one paragraph each. How many paragraphs can the full text be divided into? What is the general idea of each paragraph?

The first stage (1 ~ 4 natural stage): In the evening, I went boating with my friends.

The second paragraph (natural paragraphs 5 ~ 9): Write that when my friends and I passed by birds of paradise for the first time, we saw the "birds of paradise"-the big banyan tree.

The third paragraph (10 ~ 13 naturally): I wrote that "I" and my friends saw "birds of paradise" again the next morning.

Residents in "Bird Paradise"-the activity scene of birds.

The fourth paragraph (14 natural paragraph): The writer's praise and nostalgia for "birds of paradise".

Second lesson

Clear goal

1. Analyze the text and understand its content.

2. Understand the static and dynamic methods to describe the scenery in this paper.

3. Experience the author's thoughts and feelings of loving and praising nature.

(B) the goal completion process

1. Learn the first paragraph.

Read and say what you have read and what words you have learned.

(1) The author had dinner, and at dusk, he took a boat trip by the river with his friends. From "having dinner", "we jumped on the boat one by one" and "moving towards the center of the river", we can realize that the environment was very quiet at that time. What I learned from No Wave, Moving Quietly, and Hearing Underwater Sound)

(2) Practice reading aloud and experience the author's happy mood when playing.

2. Learn the second paragraph:

(1) Show slides (illustrated in the text).

Look at the picture and sum up what kind of big tree it is with a word or a phrase.

A tree has turned into a forest, full of vitality and lush ...

(2) Silent reading thinking:

In what order did the author describe banyan trees?

What are the main characteristics of banyan trees? Draw a line with _ _ _ _ _ _ _.

(3) Group discussion and mutual communication:

This paragraph describes the characteristics of "big" and "beautiful" banyan trees. Sentences describing "big": ① "In one place, the river narrows." (2) "The banyan tree is so lush that you can't see where the trunk is." When I talk about many banyan trees, I have seen many banyan trees, and this is the first time I have seen such a big one. Sentences describing "beauty": ① "Clusters of leaves" ... are so lovely green ". 2 "There are many roots hanging to the ground ... lying on the water." (3) "So many green leaves ... new life is trembling." )

(4) Graphic contrast "Students communicate, teachers guide and understand key sentences:

Slide show 1:

These two sentences describe the true face of this big banyan tree. The characteristic of a tree is that its roots are on the branches. The roots on the branches "hang down to the ground and plunge into the soil" and then become the trunk, which is why there are countless branches on this big banyan tree.

(5) Instruct reading aloud and cultivate students' ability to experience and appreciate beauty.

(6) Summary:

In this passage, the author describes the size of the banyan tree, and describes the shape, color and size of the roots, leaves, stems and branches of the banyan tree from far to near. This is a static description.

3. Learn the third paragraph:

(1) Read the third paragraph by name.

Thinking: What does this paragraph mainly say?

This passage mainly describes what the author and his friends saw when they passed the "Bird Paradise" again the next day. )

(2) Rereading the discussion, teachers should give timely guidance:

Re-read and think:

How does the author describe the activity scene of birds flying? Mark the relevant sentences and understand the author's mood at that time.

(1) The author uses the parallelism sentence "Big, small, flowery, black, some standing on the branches, some flying, some flapping their wings." Write the shape, color and posture of the bird. Written in this same or similar sentence pattern, it has a strong sense of rhythm and is catchy.

The author used the anthropomorphic sentence "The tree has become lively." "Standing on a twig and shouting excitedly, that song is really nice." It is about the lively and free life of birds in Paradise, which reflects the author's good taste and happy mood. )

(3) Emotional reading to understand how the author describes this passage.

(4) Summary:

In this passage, the author mainly wrote about the activities of birds-birds with different sizes, different feathers and different dynamics, forming a "hundred birds map". It is a description of the changing activities of things, and it is a dynamic description.

4. Learn the fourth paragraph:

(1) Read the fourth paragraph freely.

Tell me what you read from which sentences.

From "Looking Back", "A Little Miss" and "Bird's Paradise is indeed a bird's paradise! Realize that the author's mood is happy and feel nostalgic. )

(3) Emotional reading to deepen understanding

Read homesickness and praise. )

(3) Homework after class

1. Read this text with emotion.

recite a text

From "our ship is approaching the banyan tree" to "this beautiful southern tree" )

The third category

Clear goal

Grasp the key points and learn to express.

(B) the goal completion process

1. Transition:

Through the study of last class, we learned that this text describes the different scenes that the author saw when he went to "birds of paradise" twice according to the tourist route. The two-day trip has different emphases and methods. So how did the author write what he saw and heard? This is the focus of our study in this class.

2. Projection display self-study outline: silent reading and thinking

Centralized communication and arrangement

(1) The time is different: the first time is in the evening and the second time is in the morning. I didn't see any birds on my first trip because it was getting late and the birds had settled in the tree. The second time I went to see many birds, because in the morning, the birds began to move.

(2) Because this banyan tree is very big, with lush foliage, moist land and peaceful environment, it is just suitable for birds to nest, and farmers are not allowed to catch it. Birds are protected and easy to breed, so it has become a "paradise" for birds to live.

3. Read the text again and discuss the communication.

(1) Where is the static description in the text? What are the dynamic descriptions? What are the advantages of writing like this?

① The big banyan tree is static. The author writes one by one from its roots, stems, branches and leaves, which is a static description of the banyan tree. For example, "the number of branches is uncountable. The branches took root again, and many of them fell to the ground and plunged into the soil. " The green leaves are layered, leaving no gaps. ""Green shines brightly on our eyes, as if there is a new life trembling on every green leaf. "

② The scene I saw in Bird Paradise for the second time mainly described the activities of birds, which was a dynamic description. For example, "Birds are everywhere, birds are everywhere. Big, small, flowery, black, some standing on branches, some flying, some flapping their wings. "

③ When writing an article, paying attention to dynamic description and static description can make the content more specific and accurate, and the combination of dynamic and static can enhance the appeal of the article.

4. Read the text aloud to deepen your understanding.

(3) Summary and expansion:

1. Summarize the full text and summarize the center.

This paper describes the different scenes that the author and his friends saw when they passed through the "bird paradise" twice, and shows that the beauty and strangeness of the big banyan tree and its being called "bird paradise" are well deserved. It expresses the author's thoughts and feelings of loving and praising nature. )

2. What inspired you after learning this text? The answer is not unique, students can speak freely. You can know the content of the article, learn the writing method of this article or talk about loving birds and protecting the environment. After learning this text, I learned that observing things should not only pay attention to the size, shape, color and position of things, but also pay attention to the static and dynamic changes of things in different periods. )

(4) Transfer

1. Extract good sentences.

2. Draw a static sentence with the line "-"in the essay and a dynamic sentence with the line "-"in the essay. The frog's two big eyes protrude high, like two crystal glass balls. It is very clever. As soon as I put it in the basin, my long webbed hind legs shrank back, and with a whoosh, it jumped out a long way and splashed a little.

reference data

1. banyan: a multi-branched evergreen tree with a large crown, oval or oval leaves and yellow or reddish flowers, which grows in tropical and subtropical regions. The perennial banyan tree can grow black roots on its branches and hang down to the ground. When it is buried in the soil, it becomes a trunk again. The leaves, roots and bark of banyan trees can be used as medicine.

2. There is a river called Tianma River on the outskirts of Xinhui County, Guangdong Province. There is a huge banyan tree in the middle of the river, which is intertwined and lush. Its coverage is unparalleled in the world; From a distance, it looks like a big forest floating on the water, attracting countless birds to live here. Locals call it "a paradise for birds".

3. Thrush: brown body, gray belly, black stripes on head, back, neck and back, white eyes, and a very pleasant cry.

Birds of paradise Teaching Design II

Xiaoyu Forum User: Zhu Baoxian

Release date: 03: 55 September 2004.

Teaching objectives

1. Understand the content of the text, feel the beauty of the living landscape in bird paradise described in the text from different angles, and enhance the awareness of protecting the ecological environment.

2. Cultivate students' ability to fully express their views in the reading process.

3. Understand the static and dynamic state of things by understanding the two descriptions in Bird's Paradise.

4. Learn the new words in this lesson. 5. Read the text with emotion. Recite some paragraphs of the text.

Teaching focus

1. By understanding the two descriptions in Bird's Paradise, we can understand the static and dynamic state of things.

2. The paradise of birds is mentioned five times in the text. Why are some cited and some not?

3. Experience the beauty of birds of paradise, and encourage students to fully express their views in reading and express their feelings in various ways they like.

Teaching difficulties

1. The students don't quite understand why the big banyan tree looks so strange. They may have questions, so they should make it clear.

2. Read the text with emotion and recite your favorite parts.

Teaching means: self-made courseware.

Teaching hours: 2 hours.

first kind

Design intention: From Ba Jin's perspective, feel the beauty of the living landscape in which man and nature live in harmony in the "bird paradise" described in this paper, and enhance the awareness of protecting the ecological environment.

Process:

First of all, talk about

1. What is heaven? (roll call answer) 2. What will the bird's paradise look like on the blackboard?

Second, study as required.

1. Read the text correctly and fluently. 2. Think about how you feel after reading the text. Write a note beside it. 3. Put a question mark where you don't understand.

Third, check the effect of self-study

1. Read the text by name, and correct the pronunciation where there are new words and phrases. 2. Talk about your feelings about reading. 3. Put forward what you don't understand. Communicate with each other.

Fourthly, introduce the author and the relevant knowledge of the text.

Ba Jin wrote this article on 1933 when visiting friends in Xinhui, Guangdong, and passed by the "paradise of birds". What is actually written in Bird's Paradise? "Bird's Paradise" actually refers to a big banyan tree about 500 years old, which is located on an island on the Tianma River in Tianma Village in the south of Xinhui City, Guangdong Province.

Five, understand the main content of the text

1. How did the author go to "Bird Paradise"? How many times? What's the difference between the time of each visit? How many times have you really watched Bird's Paradise? 2. Those sentences can best express the author's thoughts and feelings, and draw them with strokes. And talk about what feelings are expressed.

Sixth, learn new words.

1. Read the words by name. 2. Guide the writing of difficult words. 3. Copy new words.

Blackboard: 18. Bird's paradise

The first big banyan tree

The paradise of the second bird

Second lesson

Design intention: From the perspective of birds, feel the beauty of the living landscape in which man and nature live in harmony in the "bird paradise" described in this paper, and enhance the awareness of protecting the ecological environment.

Process: write on the blackboard before class.

Guide: Students, are you nervous? It must be nervous to see so many teachers sitting here. Today, the teacher made everyone become happy birds one by one. Let's learn the lesson "Bird's Paradise" (show courseware: bird map). Now, you are these birds. Are you still nervous? In this lesson, we will feel the "bird paradise" from the perspective of birds.

Through the study of last class, we know: how many times has Mr. Ba Jin been to bird paradise? What did you see for the first time? What did you see the second time? The first time I saw the big banyan tree, the second time I saw the real "birds of paradise")

Second, first of all, let's go to the real bird paradise, which is your paradise.

1. Show the courseware (12- 13).

2. Read this part freely. What are the characteristics of Bird's Paradise written in this part? (Lively and lovely, full of birds) Where did you get it? (Freedom of speech)

When students read the word "at a loss", they asked: What does this word mean? Play the courseware "Birds are Flying" to help you understand.

4. What are the main features of this paragraph? (Lively) Yes, this is its dynamic beauty. This paragraph mainly describes the development of birds of paradise. Let's interpret its dynamic beauty together. Read "Some ... Some ... Some ..." and "A thrush ... That song is really nice ..." to read the loveliness of birds; Read more about birds by reading "Birds everywhere, birds everywhere" and "Too many things to see ...". )

5. After reading, the student asked: This bird is chirping excitedly. What is it saying? I am really happy here. If you are that bird, why do you like this place? Let's focus on the big banyan tree, the environment where birds live.

Third, show the courseware and learn the first part: (paragraphs 7-8 of the text)

1. Read this part freely and find out why birds like this place. Write a note next to the relevant sentences in paragraphs 7-8. Mark what you don't understand.

2. Discuss in groups why birds like this place. Where can you see it?

3. Class communication. This tree is big and beautiful.

A, when students talk about the big and beautiful characteristics of trees, show courseware to help students understand.

B, when students talk about the words "uncountable" and "lying", show courseware to help students understand.

C. Is there anything you can't understand? Say it and discuss it.

D. If not, the teacher wants to ask a question and show the courseware: "Every green leaf has a new life trembling." I don't understand what "new life is trembling" means. Why does the author feel this way?

1. Student discussion; (understand in context. The reasons may be as follows: ① there are many leaves, and birds move when they flap their wings; ② "The banyan tree is in full bloom, and it seems to show us all its vitality." (3) The wind blows. )

2. Show the courseware to understand.

E. what do you think of such a beautiful tree?

Read paragraphs 7-8 by name. Comment: How is your reading? Do you want to listen to the teacher?

How does the teacher read it? When reading the paragraph 12- 13, we ask to read the dynamic beauty of bird paradise. How should these two paragraphs be read? (reading its quiet beauty)

Read it together.

Students have a strong reading ability. If you are a bird, how do you feel when you see such a beautiful big banyan tree? Do you want to tell your partner this feeling?

Now, the teacher wants you to write one or several advertising words for the big banyan tree as a bird to let your other half know that it is beautiful here.

Students write advertising words.

Communicate with each other.

Seven, the advertisements written by students are really beautiful, which gives teachers a sense of happiness. But, you see, what did the teacher forget to write on the blackboard this class?

If you don't want the teacher to be defective, show the blackboard writing of Guilin Landscape, and design the blackboard writing for the teacher accordingly.

Students design and organize communication.

Eight, such a beautiful place, why so beautiful?

Students speak freely. Talk about environmental awareness.

Summarize the text.

Teaching Design III of Bird's Paradise

Research Group on Applicability of Experimental Textbooks of People's Education Press in Jiulongpo District, Chongqing

first kind

Teaching objectives

1. Learn the new words in this lesson.

2. Read the text for the first time and clarify the context of the article.

Teaching preparation

1. Multimedia courseware, new word card.

2. Information about banyan trees, pictures and author information.

teaching process

First, introduce topics to stimulate interest

1. Look at the topic together. What do you think when you see this topic? Where there are birds living, where there are birds in heaven, and where there are many birds ... Let the students imagine. )

2. Where is this bird's paradise? Do you know that?/You know what? Do you know that?/You know what? (A big banyan tree)

3. Introduction: Where is this big banyan tree? Can you introduce the information searched before class? This big banyan tree has a history of more than 500 years by the Tianma River in Xinhui County, Guangdong Province. Every year, it grows many air roots, hangs upside down on branches, drills into the soil, and grows new branches in a few days. This continuous growth has grown into a banyan forest with an area of 16 mu. Called "holy tree" by local people. Heaven in heaven. Because many birds live on it, it is called "bird's paradise". )

Today, let's follow Grandpa Ba Jin to see the unique big banyan tree.

Second, read the text freely and master the new words.

1. Read the text by name and read the pronunciation correctly.

2. Projection demonstration exercise: Choose the correct pronunciation in Braille.

3. Learn new words by yourself and master fonts.

Key guidance

Hint: Pictophonetic characters are different from "omitted" and "mentioned".

Leisure: on the left is "day", which is distinguished from "defect"

4. Draw words you don't understand. With the help of reference books.

Brilliant: Bright and dazzling.

One after another: back and forth, intermittent.

Display: To display clearly.

Nostalgia: reluctant to leave.

Countless: there is no way to calculate it, and it is described as a large number.

Be overwhelmed: there are many people or things to describe, and it is very difficult to receive and cope with them. Leisure: space. There are too many birds in the article to read.

Third, clear the context of the article.

1. Read the text silently and think: How many times did Grandpa Ba Jin pass by birds of paradise? What's the difference between what you see?

2. report and exchange.

Student A: The author crossed the paradise of birds twice. The first time he saw the big banyan tree, the second time he saw many birds.

Student B: The natural paragraph of Text 5-9 describes the scene when the author first passed a bird's paradise, and the natural paragraph of 10- 13 describes what he saw after the second paragraph.

3. Clear the context of the text.

(1) The author wrote it in the order of tour. It can be divided into several parts.

(2) Student report:

The text can be divided into four parts.

The author and his friends went boating.

(5-9) What I saw when I first passed through the paradise of birds.

(10— 13) I saw it when I passed birds of paradise for the second time.

(14) The author's nostalgia and praise for "birds of paradise".

Fourth, read the text in groups.

Second lesson

Teaching objectives

1. Understand the content of the text and the strangeness and beauty of the big banyan tree and the birds flying.

2. Learn the description method of the author's dynamic and static combination.

Read the text clearly and recite the favorite paragraphs.

teaching process

First, the overall perception

1. Introduction: Please listen to a piece of music first, and then tell your feelings. Play the tape of "A Hundred Birds at the Phoenix". There are many birds, a paradise for birds-blackboard writing. )

2. In this class, we will go to a place called "Bird Paradise" along the Tianma River in Xinhui County, Guangdong Province with Grandpa Ba Jin. Grandpa Ba Jin went to birds of paradise twice and saw a completely different scene. He saw it for the first time (student: big banyan tree) and for the second time (student: bird).

3. Please choose your favorite reading method to read the text quickly and experience the feeling brought by banyan tree. How do birds make you feel? (banyan tree-big and lush; Birds-many, cheerful)

Second, focus on the unique beauty of banyan trees and the spectacular sight of birds flying.

(1) Please choose your favorite part, grasp the key words, and read aloud with emotion after the experience. Report in the form of reading aloud

(2) Reporting and communication.

Big banyan tree:

1.

Student A: I have a chance to see it for what it really is. This is really a tree with countless branches.

(1) report reading, other students listen: where did you read well? Why? What did you hear? Where did you hear that? From countless experiences, there are many branches, which shows that the tree is very big. )

(2) Focus on the word "true".

What's the difference between two "truths"? Listen to the teacher and experience.

Show me the projection:

Students realize that the first meaning of "truth" is original and practical. The second "true" means true. You should read the tone of surprise.

Student B: The branches have taken root again, and many of them hang down to the ground and plunge into the soil.

(3) Focus on the word "you". There are many roots.

Show me the picture: Who will point out which are the air roots? (Experience that branches grow on roots, roots grow on branches, and a tree becomes a forest landscape. )

Student C: Some branches hang down into the water. From a distance, it looks like a big tree lying on the water.

(4) Understand the word "lie". Trees cover a large area. )

(5) How big is this big banyan tree? Who discovered this information? (Student A: More than 10,000 square meters. )

(6) After class, we measure the area of the playground and classroom. Let's calculate: How many playgrounds are there? How many classrooms? Ask the students to answer according to the specific situation. )

(7) How do you feel after the conversion? (It's simply too big. )

2. lush. Name the sentence and talk about your experience.

Student A: There are so many green leaves, one on top of the other, leaving no gaps. There are many leaves without leaving gaps. )

(1) The emphasis is on "pushing". Please prove that there are many dense leaves.

Student B: The green of the earth shines brightly in our eyes. It seems that every leaf is shaking with new life.

(2) Pay attention to "tremor".

Students prove that it is slightly dynamic.

From this, we realize that the vitality of banyan trees is very strong. )

Student C: From the description of the characteristics of the big banyan tree, we can see that the author can't help sighing in his heart: this beautiful southern tree.

3. Watch the video: the size and luxuriance of banyan trees.

4. Ask students to read this part of the content repeatedly, highlight the key words, experience the characteristics of banyan trees, and express their understanding and feelings about the content of the text during reading.

5. Let the students draw a picture on the blackboard, reflecting the characteristics of banyan trees.

bird

1. Play the courseware video: the scene of Birds Flying. Let the students vividly feel the description of this part of dynamic beauty.

2. Introduction, let's walk into the text and enjoy the lively scene. Please choose your favorite way to read the text and enjoy the beauty depicted in this part.

3. Read the text silently and think: From which key sentences can you realize that there are many birds here?

4. Student report.

We continued to clap our hands, and the trees became lively. There were birds everywhere, birds everywhere. (Two "everywhere" means there are many birds. )

I watched intently, my eyes at a loss. I saw this clearly, missed that again, saw that, and the other flew again. To be at a loss means to have too many people or things to deal with. According to the text, there are too many birds to watch. )

The big ones, the small ones, the flowered ones and the black ones all stood on the branches, screaming, flying and flapping their wings. (some ... some ... some, indicating that birds have many postures and many kinds. )

A thrush flew out ... it stood on a twig and cried excitedly. This song is beautiful. I feel that the bird is very cheerful and chirps happily. )

5. Teachers take the opportunity to guide and stimulate students' imagination.

So, please imagine, what posture is there in the tree? (Students expand their imagination. )

6. What kind of sigh did the author give when he saw such a strange banyan tree and enjoyed the scene of birds exulting on it?

Students read together (projection demonstration)

It was my eyes that deceived me yesterday. "Bird's Paradise" is indeed a bird's paradise!

7. The teacher asked:

(1) What do you find from this sentence? The first Bird's Paradise has quotation marks, but the second one doesn't. )

(2) Why does the author write like this? What are the different meanings?

The first bird's paradise refers to this big banyan tree, and the second bird's paradise refers to the real bird's paradise. Birds inhabit and breed here and live a happy life. )

8. With the cheerful music, let the birds painted in the art class fly to the big banyan tree.

9. Read this part of the text again and experience the lively and cheerful scene.

Third, understand why banyan has become a paradise for birds.

1. What makes this big banyan tree a "paradise for birds"?

2. Students introduce and analyze according to the extracurricular materials or other knowledge they have found.

3. Summary: The luxuriant branches and leaves of Ficus provide living space, food and water for birds. Local residents love birds, and bird droppings become organic nutrients for the growth of banyan trees. Let this banyan tree grow more luxuriantly.

Fourth, broaden the thinking and deepen the theme.

1. Play the complete courseware of birds of paradise.

2. Show me the thinking question:

Please introduce the scenic spots here to tourists as a tour guide or a bird. The form of introduction can be freely chosen. For example, writing tour guide words, writing poems, and running smoothly.

3. Students prepare separately.

4. Students choose their favorite way to express their learning feelings. Report and communicate.

Verb (abbreviation of verb) is a summary of the whole text.

The big banyan tree has been endowed with exuberant vitality by nature and has become a paradise for birds. As human beings, we should also protect animals. Protect the environment and nature.

Attachment: blackboard design