Computational thinking and programmingkey stage 2
Subject content for KS2
Pupils should be taught to:
• design, write and debug programs that accomplish specific
goals, including controlling or simulating physical systems;
solve problems by decomposing them into smaller parts
• use sequence, selection, and repetition in programs; work
with variables and various forms of input and output
• use logical reasoning to explain how some simple
algorithms work and to detect and correct errors in
algorithms and programs
Decomposing problems
“solve problems by decomposing them into smaller
parts” - Subject content KS2
Decomposition is the process of breaking a problem
down into smaller problems so that ultimately the
bigger problem can be solved (and explained clearly to
someone else or to a computer).
Sequence, repetition &
selection“use sequence, selection, and repetition in programs” - Subject
content KS2
Sequence: putting instructions in an order where each one is
executed one after the other
Repetition: one or more instructions are repeated a number of
times or until a condition is met or the program is stopped
Selection: instructions are executed depending on whether a
particular condition is met
Selection lies at the heart of the ‘intelligence’ of a computer
program.
Activity #1 Hour of Code
Working in pairs, follow the Hour of Code beginners
tutorial. Your challenge is to complete this in 30 mins!
http://learn.code.org/hoc/1
NB: This tutorial introduces the key programming
concepts of sequence, repetition and selection
Debugging at KS2
“design, write and debug programs that accomplish
specific goals” - Subject content KS2
This builds upon children’s experience of debugging at
KS1. As their programs become more sophisticated
the debugging becomes more challenging.
Activity #2 Scratch Roamer
View the Simple Roamer project at
http://scratch.mit.edu/projects/33560452/. Click the
green flag to make the Roamer move.
Can you write a program to make the Roamer draw an
equilateral triangle? Click the ‘See inside’ button to get
started.
Hungry Monkey
View the Hungry Monkey project at
http://scratch.mit.edu/projects/21416773/. Click the
green flag to play the game.
We’re now going to decompose this game into smaller
problems and you will learn how to program each
element.
Activity #3 Hungry Monkey 1
http://scratch.mit.edu/projects/34307992/
Can you make the monkey sprite move left and right
when the left and right arrow keys are pressed?
Hint: you need to use a ‘forever’ block.
Activity #4 Hungry Monkey 2
http://scratch.mit.edu/projects/34309136/
Can you make the monkey jump when the ‘up’ arrow
key is pressed?
Hint: you’ll need to use a ‘wait’ block.
Activity #5 Hungry Monkey 3
http://scratch.mit.edu/projects/34311270/
Can you hide the bananas when the monkey grabs
them?
Hint: you’ll need to copy the code from Sprite1 to the
other banana sprites. To do this, drag the code stack
from Sprite1 onto each of the other banana sprites.
Variables
“work with variables” - Subject content KS2
Variables are containers for data. They enable us to
store, retrieve or change data. A variable could be
used in a game to keep track of a user’s score or to
remember a player’s name.
Activity #6 Hungry Monkey 4
http://scratch.mit.edu/projects/34312402/
Can you make the score board work so it keeps track
of the number of bananas the monkey has caught?
Subject content for KS2
Pupils should be taught to:
• design, write and debug programs that accomplish specific
goals, including controlling or simulating physical systems;
solve problems by decomposing them into smaller parts
• use sequence, selection, and repetition in programs; work
with variables and various forms of input and output
• use logical reasoning to explain how some simple
algorithms work and to detect and correct errors in
algorithms and programs
Follow up from today:
Turvey K. et al. (2014) ‘Programming and
computational thinking’ in Primary Computing and ICT,
Knowledge, Understanding and Practice, London:
Sage.