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RevisionLesson

Scratch A

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In this lesson you will learn:General practices to avoid strain on your fingers while using the keyboard Exercises for strengthening wrists, neck and spine.Eye exercises

mAi

Moz: Telugu and Marathi. Good to see you learning more languages. Tejas: Moz, Does the computer understand the languages that we speak?Moz: Yes. It understands a few languages. But the number of words and the sentences that it understands are limited. Jyoti: It is just like a robot.

Tejas: Ok.Moz: Jyoti will give you instructions to move from the place that you are now using the limited instructions.Tejas: Yes. As I move I will hold a chalk piece down so that you can see how I moved.

Moz: Yes. Suppose Tejas understands only the following 5 statements.Move forward -- steps, change direction to north, change direction to south, change direction to east, change direction to west.

Good morning, Good bye.

What is your name? My name is -----.

Where do you stay? I stay in Mumbai.

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Tejas: Look at the square which shows Tejas’s trail!! Jyoti: Does computer understand these instructions? Can we use some pictures? Tejas: Which application do we use to give the instructions?

Tejas and Jyoti first discuss the limited instructions that they have. They decide to give instructions to Moz to move on a square. They write the step by step instructions. Then they convert the movements into the limited instructions.

1Change direction north

2Move forward 10 steps

3 Change direction to west

4Move forward 10 steps

5Change direction to south

6Move forward 10 steps

Change direction to east7

8Move forward 10 steps

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Tejas: Look. These instructions are similar to the instructions we gave to Moz. Jyoti: Moz, How do we make the computer follow these instructions?

Jyoti: Oh! Look the cat is moving and a trail of the cat is shown.Moz [points to the stage area]: This area is called the stage, similar to the stage where you perform. The computer follows the step by step instructions to give the output for your instructions.

Moz, Double clicks on the block of the instructions. The cat moves and a square is drawn.

Moz: You will see the instructions that the computer understands which are similar to the above. Yes you can use pictures. Moz: Scratch has instructions that the computer understands.

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Tejas: So, this is where we write the instructions?Moz: Correct. This is called Scripts area. The step by step instructions are given here.Jyoti: And the cat performs step by step all the instructions!Moz: The cat is called the sprite.

SKILLS

SKILLS

StageThe Stage is where you see your stories, games, and animations come to life.

Scripts areaScript is the step wise instructions you give to the sprite to do a particular task. Scripts area is the place where you write the script for the sprite.

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Jyoti: Are these the instructions that the computer understands.Moz: Yes.Jyoti: But there is no “pen down” instruction here.

Jyoti points to the pen and says,Jyoti: Let me click on pen and see what happens.

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Jyoti: Oh! This is just like paint. Each option gives a different set of instructions. All the pen related instructions are grouped together here.

Tejas: Yes. All the movement related instructions are listed when we select motion option.Moz: Good observation.

SKILLS

SKILLS

Pen block has instructions to give a trail of the sprite, to change the colour of the trail etc.,

Motion block has instructions to make the sprite move, like number of steps to move, direction to move, etc.,

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Tejas: Jyoti, let us use try drag and drop to put the instructions in the scripts area.

Jyoti: This is good. And when we bring one instruction below another it pastes itself to form a block.

Moz: Correct. When you put all the instructions together it is called a block of the program. Explore the instructions in the options “Motion”, “Pen”.

Tejas and Jyoti try out the following instructions using motion and pen and run the block of the program.

SKILLS

To write a Scratch program (the detailed instruction set for the sprite) we have to just drag the instructions (graphic blocks) for motion, sound, etc from the blocks palette area and drop them into the scripts area. These graphic blocks are pasted one after the other which is called a script. When you double-click on a script, Scratch runs the blocks from the top to the bottom of the script.

Pictures for Drag and drop of scripts to scripts area.

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Tejas: Jyoti, we can change the number of steps the sprite moves, by deleting the number and adding the new number.

Jyoti: Yes, and we can change the direction by clicking on the arrow and selecting the direction.

Tejas: Let us try the sound block instructions now.

Tejas: Do we always have to use the cat as the sprite.Moz: There are some sprites that are available by default. You can use these or you can even

draw your own sprite and use it. Moz: Click on this button to get a list of available sprites, from where we can select a new sprite.

SKILLS

Sound block has instructions to make the sprite speak, and also add musical sounds etc.,

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SKIL

LS

To add a new sprite

Click on to paint a new sprite.

If you want to select a sprite from the existing list of sprites, click on to you will get the list of sprites and select one.

Clicking on this button will give you a surprise sprite.

To delete a sprite, select the scissors from the Tool bar and click on the sprite or right-click on the sprite and select delete from the pop-up menu.

Moz: To change the look of the sprite you can use costumes.Jyoti: Can we use more than one costume for a sprite. Moz: Yes. You can.Tejas: The instructions to change the costume are in the costume block!Moz: Correct.

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Tejas: That was fun. Jyoti: Can we make the sprite repeat the actions? Moz: Yes, you can and you can also control the way the script is executed. Next time we will explore these features of scratch. Chin chinaki...

Jyoti: This is fun. Let us use the instructions in motion, pen, costume and sound and make a program.

Tejas and Jyoti write the instructions and run it.

Lesson

Outcome

After you have studied this lesson,

you will be able to:

Understand how some simple

practices and exercises help to

avoid strain on fingers, eyes and

back while using a computer.

Learn how to position the fingers

on the home row of the keyboard

and type with many fingers.

Step by Step execution of the instructions. Usha: Here we can have it in the screen style the program and the execution.

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WORKSHEETSBook III Lesson 3

1. Write the following program in scratch and save the project:

2. Write the following program in scratch and save the project:

3. Write the following program in scratch and save the project:

Add the following to your script:a. Change the costume of sprite.b. Change the background stage.

Add the following to your script:a. Sound of an instrument.b. Dialogue from the sprite as a callout.

Add the following to your script:a. Change pen colour to blue.b. Change pen size to 10.c. Decrease the number of steps to change the size of the square.

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WORKSHEETSBook III Lesson 3

4. Write the following program in scratch and save the project:

5. Write scripts for the following program

Add the following to your script:a. Track the sprite’s move using pen down.b. Change the dialogue inside the ‘think’ box. c. Change the dialogue inside the ‘say’ box.

Do the following:a. Increase the size of the sprite.b. Decrease the size of the sprite.c. Change the background.d. Draw a new sprite.e. Save your project.

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WORKSHEETSBook III Lesson 3

Find: a. How to run the script on the full screen stage.b. [Hint: Enter presentation mode]c. How to get a surprise sprite.d. Save your project.

6. Write scripts for the following programs

7. Write a program to show the following:

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Book III Lesson 3

1. Draw a sprite using Paint editor in Scratch. Select different colours, brush tool to draw the picture. Use the stamp tool and the eyedropper tool.

Group ActivityTo do this activity, divide the class into groups of five students each. Get Rangoli powder (coloured powder) and spread it on a sheet of a newspaper. Now take a wet sponge and dip it in the rangoli powder. One student has to draw a picture on the chart paper as per her group’s instruction. Each group draws different pictures such as sun, mountains, farm, etc. The teacher discusses the steps involved in doing the activity, compares it to giving instructions to the computer using scratch.

2. Use the picture your draw and write a script. Save your project. Write a story to show what is happening in the project.

3. Write a script to show ___________ asana.

Explore!1. Find out how to make the sprite move in a circle.

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Teacher’sCornerBegin the class with playing a game. Blind fold one student and ask other students to give her directions to do an activity. For example, pick up a chalk from the table and write something on the blackboard. You can also draw a picture of an animal and ask the student to draw its tail. Note that other students are supposed to give directions to do the activity. Explain that doing the activity requires step by step instructions to their classmate. Just as we follow the instructions, the computer also needs instructions from us to do the activity. What we call step by step instructions; in computer language it is called programming.Encourage the students to discuss what a particular object is called in their mother tongue. You will come across a variety of names for that object. Ask the students to imagine that they are visiting their friend’s grandparents, who do not understand your language. How will you communicate with them? The students might say that they will use non-verbal signs to convey what they are saying or take help from their friend. Inform the students, that just as you need to learn a few words of the language to communicate in the new region, you need to learn the language of the computer.Introduce scratch as an interactive language of the computer. Explain that the sprite is like your blind folded friend, who needs proper instructions from you to do the activity. Demonstrate how you can make the sprite move 20 steps and changedirections. Ask the students if they want the sprite to make a sound as the activity is done. Import the sounds and add it from the stack of blocks. [Ensure that the speakers are connected]. You may also show them how to introduce a callout to make the sprite say or think something. Let the students give you the dialogue for the sprite. Ask the students if they want another sprite. Demonstrate how to get the new sprite or create a sprite using the paint editor. You can ask the students to explore the options on their own and figure out how to change the background. Explain that sprites sounds and backgrounds are stored in sub-folders. The names of the sub-folders convey its contents, for their convenience. Revise the concept of folders and sub-folders. Ask questions such as “What would happen if the sub-folders were not used and all of them were placed in a single folder?” Encourage students to think and reason out the necessity of organising files into folders.Explain that the instructions are placed in the appropriate blocks. For example, all the instructions about pen down are in the block called ‘pen’. Similarly, all the instructions for sound are in the folder called ‘sound’. Demonstrate the use of pen down and write a script to draw a square. Explain that the instructions given to the sprite is called script. This can be saved as project in the appropriate folder. Summarise the lesson and ask the students to write their projects. You can ask them to write a story about the project they created.You can end the class by asking students to do an exercise where students move their hands in the different directions --- forward, right, left, up, down, backward directions are given. Change the sequence of directions and make the game enjoyable. [In case of space constraints, ask them to move their neck instead of hands.]

Further Reading : scratch.mit.edu

Book IIILesson 3