revision

A computer is really a system.

It is a combination of two very different parts.

Neither part is any use without the other.

Hardware + Application = computer system

Computer programmers are perfectly normal people who are lucky enough to do a creative job which fascinates them.

Is programming difficult?

Quick revision

A Background is just an image that is placed on the Scratch stage - it could be a picture drawn using paint or a photograph downloaded from Google images.

Log into your Scratch account and click on the Create tab.

You will see the Scratch project editor screen shown below.

It is divided into five sections:

Costumes - Learn how to create your own sprite and two different costumes for the same sprite.

Backgrounds - To create a background for your program, you have the options of choosing one from the Scratch library, drawing one of your own, uploading an image that you have saved on your Google drive or taking a snapshot.

Script blocks - Scratch is programmed using pieces of script known as blocks.

There are 10 different blocks paletts in Scratch 2:

• Motion - moving a sprite and X Y co-ordinates

• Events - when something happens

• Looks - setting costumes and text

• Control - starting and ending programs, loops and conditions

• Sound - adding simple sound effects (you can even record your own)

• Sensing - mouse control, sensing and timing

• Pen - drawing lines

• Operators - calculations and operations

• Variables - setting and using variables

• More blocks - make a block or add an extension

No matter which language you use, there are certain techniques or constructs that you will need to learn to make your programs more sophisticated.

Read on to learn about some of the most important constructs

Controlling position and motion

To bring your characters to life you are going to make them move.

Practise some of the things that you were taught in the video.

Were you able to make a Sprite move?

Create an animated character (it can be a person, an animal or an alien being) using a single sprite with two costumes. Make it move across the screen changing costume as it goes.

Were you able to use a Repeat Loop to make the cat move across the screen

Remember, Scratch uses X and Y coordinates to position a character on the screen.

i) Control a sprite using the arrow keys.

You can use the mouse to move a sprite. That is how the girl is moved in the Pony Game.

To see an example of the mouse being used to move a sprite, search for and open the Scratch file, sjcs_pony. Click Remix to make it your own for hacking.

Lesson 8 - Carrying out calculations / Using operators

Operators

Operators can be used to make a program do some maths.

You met the > (greater than) operator in the previous lesson.

Other operators are:

• + (add)

• x (multiply)

• - (subtract)

• < (less than)

• = (equals)

• / (divide)

You can do a lot of maths with these few operators.

Study the Maths cat program script below.

first_number, second_number and result are the three variables in this program?

Update your your Scratch Programming Progress Record before you move on to the next lesson.

Hacking Games

One of the best ways to learn to program is to 'hack' code created by someone else.

This is perfectly acceptable so long as you have the creator's permission to do so.

You can open these games from Scratch 2 - do a search for them and then Look inside.

Hack them to learn some of the constructs used to make them.

• sjcs_pony

• sjcs_racing_game

• sjcs_maths_cat

Click Remix to make them your own for hacking.

Multiple Sprites

Search for and open the Scratch file, sjcs_aquarium

Click Remix to make it your own for hacking.

Many games make use of multiple sprites with the same or similar properties. There is no need to program each sprite separately - just program one and then duplicate it.

You can tweek the code later if you want each sprite to do something slightly different.

Watch the video below to find out how to duplicate a script for two or more Sprites.

Congratulations - you have completed all 11 lessons!

Update your your Scratch Programming Progress Record and move onto the Scratch app development project.

Review a Scratch game

Reviewing

You will have the opportunity to review a game that was developed by someone else.

For each game you review, complete a new Computer Game Review Report.

As you review a game, write in your name as the Reviewer and the name of the person who developed the game as the Developer.

Comment on two things that you particularly liked about the game.

Give one tip that might help the Developer to improve the game if they have more time.

Rate the game out of 10 (10 is the top score).

NB Write neatly and clearly, you will get a star for each game you thoroughly review.

Extension Work