1. Computing Year 7 - Unit 2
Programming Basics
Scratch Basics

2. Today’s Objectives 1
Know how to use blocks in scratch to give execute instructions 2
Know the first of our ‘Big 3’ - sequencing 3
Know that sequencing is about placing instructions in the correct order 4
Know how to debug – test a program
Practical Tasks: Make some basic programs

3. Sprite
Blocks
Instructions
Test & Debug
Stage

4. Stage
Drawers
Script
Blocks

5. Stage - coordinates 180 +y -240 240 -x +x 0,0 -y -180
10/11/17
Scratch - Programming
180
x= y=
180 x= y=
-240 x= y= +y
240
x= y=
x= y=
-180
-240
240 -x +x
Stage coordinates
0,0 -y
-180

6. Algorithm - Script Move forward then backwards Move forward 4 steps
Instructions have to be more precise
Move forward 4 steps
Wait 2 s
Move backward 4 steps

7. Different instructions giving a same output
Test & Debug
Events
Control
Motion
Move forward 100 steps
Wait 1 s
Move backward 100 steps
Different instructions giving a same output

8. D C A B Algorithm - Script Rules: Don’t change the sprite
When the sprite is clicked, start in the centre move to A and back. Do the same for B, C and D D
Rules:
Don’t change the sprite
Don’t change the background C A B

9. Big 3

10. “explain the code and problem to the duck
“explain the code and problem to the duck. This can help with de-bugging”

11. Sequencing Challenges
Make Scratch cat jump up and down when is pressed.
Make scratch cat say ‘meow’ wait for a bit and then walk to left edge of the stage when key is pressed.
Make Scratch cat say ‘I’m growing’ and grow from normal size to 200% in stages when the key is pressed.
Make one up… for
[1]
[2]
[3]
[4]

12. Challenge [1]
Make Scratch cat jump up and down when is pressed. A B C D

13. Challenge [2]
Make scratch cat say ‘meow’ wait for a bit and then walk to the left edge of the stage when key is pressed. A B C

14. Challenge [3]
Make Scratch cat say ‘I’m growing’ and grow from normal size to 200% in stages when the key is pressed. A B C

15. Big 3

16. Today’s Objectives 1
Know how to use blocks in scratch to give execute instructions 2
Know the first of our ‘Big 3’ - sequencing 3
Know that sequencing is about placing instructions in the correct order 4
Know how to debug – test a program
Practical Tasks: Make some basic programs