ICT SCHEME OF WORK
Modelling on screen in LOGO
Yr 4: Unit 4E
Class:
PoS: KS 2 1c 2a 2c
Modelling effects on screen
Date:
Theme:
Children learn to enter instructions to control a screen turtle and will compare the operation of the screen turtle with
a floor turtle. They learn how to write a procedure that ‘teaches’ the computer a new word and will be asked to
write short sequences to produce particular shapes on screen. They understand that screen steps are smaller than
floor turtle steps and will be asked to repeat procedures to produce ‘crystal flowers’ by rotating the screen turtle
through 360 degrees
Where the unit fits in:
This unit build on unit 2D ‘Routes: Controlling a floor turtle’
This unit assumes that children
•
Understand numbers larger than 100
•
Know that degrees measure turns and understand that 90, 180, and 360 degrees are quarter, half and full turns.
Vocabulary:
Listed on each lesson plan.
More obvious curriculum areas
•
Mathematics: shape and space
Resources
• A floor turtle
• A version of LOGO a free version of LOGO at www.softronix.com
or any logo program such as BlackCat Logo
•
•
Worksheets to record sequences
Graph paper
Expectations
At the end of this unit:
Most children will: create a ‘flower’ using one shape & rotating it; use the repeat instructions to duplicate the
shape; change the angle of turn
Some children will not have made so much progress and will: work from an example ‘flower’ & change the
procedure to create their own ‘flowers’; make mistakes & need to amend their work
Some children will have progressed further and will: create a ‘flower’ using more than one shape & rotating
them; use the repeat instructions to duplicate the shapes.
CEA@Islington - ICT Scheme of Work: p1 of 11
These lessons are based on MSW Logo, a free version of LOGO at
http://www.softronix.com/, although the commands used should apply to other
versions of LOGO.
There is a useful guide on using LOGO, written by Mark Warner –
http://www.teachingideas.co.uk/ict/contents.htm this has been attached to the lessons.
These lesson plans were taken directly the Kent LEA website http://www.kented.org.uk/ngfl/teaching/ict-ideas.html they were written by Helen Smith.
There are also additional lessons available on the same site –
written by Lynn Milliss, Hildenborough Primary School –
we have not included these as we didn’t want to overload teachers – but do take a look.
http://www.kented.org.uk/ngfl/hildenborough/year4.html
Techniques
To transfer floor turtle instructions to the screen and understand common language
To type commands in immediate mode
To write a list of commands to produce a pre-drawn shape
To use pendown and penup to move the turtle
To use the repeat command
To use and change a pre-written procedure
To write a procedure that uses other procedures to produce a result
Understanding
The screen turtle can be moved on screen
The screen turtle obeys the same language commands as the floor turtle
The screen turtle can be given commands to produce a specific shape on screen
The turtle can be moved before it starts drawing
The instructions can be repeated
Groups of instructions can be named
Procedures can call other procedures
CEA@Islington - ICT Scheme of Work: p2 of 11
YR4: Unit 4E – Modelling effects on screen
Lesson
Resources
Activity
1. Introduction
to Logo
Large display (see weekly plan) with
marker pens. Plastic or card shapes.
Individuals record work on a centimetre
grid – see below.
Main activity
On the large display, demonstrate FD 25. Repeat this, then RT 90. What will the turtle do if we
enter FD 25 again? Ask a child to come up and try. Stress the importance of the space between the
command and the value.
Using FD, BK, LT
and RT to draw
paths and construct
a square.
Revision / oral
What is special about a square? Are these
squares? Why / why not?
How can we make the turtle go back to the start? (Turn has to be determined from the turtle's
viewpoint.) Alternatively, we could tell it to retrace its steps. Introduce BK, LT.
What is the sum of the angles? What are
the angles of the rhombus? How can we
measure them? Is there a name for all of
these shapes?
Pupils may recall using the Roamer. Ask
them, 'What did it do? What command did
you give it to make it do that?'
Key vocabulary
Square
Rectangle
Rhombus
Quadrilateral
Command
FD (forward)
BK (back)
RT (right)
LT (left)
CS (clear screen)
REPEAT
Select pupils to work on available computers. Give them the How to... sheet. Others will work on
paper. Ask them to draw a 'staircase' and 'flag'. Use the scale 1 cm = 25 turtle units. Record the
turtle commands.
Bring the class together again to try their suggestions. Look at the flag: what shape is there? How
was it drawn? There is a quicker way. Show how to draw a square with REPEAT.
Support
Work with a group using the Roamer. Remind them of the commands and the different step size forward 1, not 25! Move round a square - pace it out ourselves first. Focus particularly on which
way the Roamer needs to turn when it is facing you. For example, turning it to your right means a
left turn for the Roamer.
If plastic or card shapes are available, children may trace their fingers round the edges to 'feel' the
corners.
CEA@Islington - ICT Scheme of Work: p3 of 11
YR4: Unit 4E – Modelling effects on screen
Lesson
Resources
Activity
Challenge
Design other 'paths' which include squares:
Plan on paper first, using the scale 1 cm = 25 units.
Plenary
Individuals report on their work. Try their ideas. What will happen if you try:
REPEAT 4 [FD 50 RT 45]
How could this be modified to draw - which shape?
Arrange for all to try out their work on the computer before the next lesson.
CEA@Islington - ICT Scheme of Work: p4 of 11
YR4: Unit 4E – Modelling effects on screen
Lesson
Resources
Activity
2. Turtling
Triangles
Large display (see weekly plan) with
marker pens. Protractors. Plastic or card
shapes: triangles.
Individuals record work on plain paper.
Main activity
How are we going to tell the turtle draw an equilateral triangle? The turtle is facing up the screen.
Draw the possibilities with a marker pen:
Find the angle that
the turtle turns in
drawing an
equilateral triangle.
Revision / oral
Revise the interior angles of a triangle.
Recap drawing a square with Logo.
If two angles of a triangle are both 70
degrees, what is the third angle?
If the first angle is 85 degrees and the
second is 25 degrees, what is the third
angle?
Key vocabulary
Interior angle
Exterior angle
Equilateral triangle
Facing
Heading
Focus on the turtle facing a particular direction. The screen display enables the whole class to see
this. Children need to identify the angle that the turtle has to turn through. They need to see the
shape from the turtle's viewpoint.
The class work on plain paper, drawing the triangle with the help of a protractor, then writing the
commands below. Draw the class together to try out some of their 'programs'. It's very likely that 60
degree turns will feature:
It's important to establish an atmosphere where children are not afraid to make mistakes, but where
they see that feedback from the computer is helpful in planning the next step.
Support
Some children find it difficult to relate to the turtle's angle of turn. Ask them to pace round a triangle.
Extend an arm in front, to show turning. Is it more or less than 90 degrees? Now look at the amount
of turn in relation to the turtle's original heading:
If plastic or card shapes are available, children may trace their fingers round the edges to 'feel' the
corners.
CEA@Islington - ICT Scheme of Work: p5 of 11
YR4: Unit 4E – Modelling effects on screen
Lesson
Resources
Activity
Challenge
Other types of triangle can be drawn (isosceles, scalene). Finding the length of the third side
challenges pupils' ability to estimate in Logo units. Constructing the shape on paper and
determining a scale (e.g. 1 cm = 25 units) will help.
Plenary
Discuss why the turtle needs to turn 120 degrees, not 60. If the turtle continued to turn 60 degrees,
what shape would it draw? Can the class predict how to draw other polygons?
In every case - square, triangle, hexagon - what is the sum of turtle turns (given that it returns to
face its original heading)?
3. Turtling
Polygons
Calculate the
turning angle to
draw any regular
polygon.
Large display (see weekly plan) with
marker pens. Plastic or card shapes.
The class will record work on paper – see
below for the sheet.
Revision / oral
Revise the properties of a square. Recap
how turtle draws a square and equilateral
triangle. Remind pupils of the REPEAT
command.
Is a square a rectangle? Why?
What is the sum of the internal angles?
What do two / three angles add up to?
Are these shapes squares?
Why / why not?
Main activity
How are we going to tell the turtle draw a hexagon? Start with the turtle facing up the screen. Draw
the first side. The turtle now has to face which direction? What angle does it turn through?
When the hexagon is complete, check that the turtle is facing its original heading. What is the total
of the turns it has made?
Groups work on available computers. Individuals work on paper grids, with a table to record their
findings. First, they investigate a regular octagon. Can they see the connection between number of
sides and the turtle turn?
If the turtle repeatedly moves forward the same distance then RT 30, what polygon will it draw?
(Dodecagon, 12 sides)
Support
Ask children to mark on the sheet, then measure, the angle, which the turtle turns when it draws
the square, triangle and hexagon. Plastic or card shapes will help children to touch and hold, as
well as see the corners.
Challenge
Work out the instructions for a pentagon, nonagon, and decagon.
CEA@Islington - ICT Scheme of Work: p6 of 11
YR4: Unit 4E – Modelling effects on screen
Lesson
Resources
Activity
Key vocabulary
Regular polygon
Pentagon
Hexagon
Heptagon
Octagon
Nonagon
Decagon
dodecagon
Plenary
Look at the completed table:
Name
Equilateral triangle
Square
Hexagon
Octagon
Number of sides
3
4
6
8
Turn (degrees)
120
90
60
45
Total turn
360
360
360
360
What is the rule for telling the turtle to draw a regular polygon? How do we draw a pentagon? Test
some of the children's suggestions.
Computer groups: how could we draw a circle (or a shape with so many sides it looks like a circle)?
Arrange times before the next lesson where all children can try their instructions on the computer.
CEA@Islington - ICT Scheme of Work: p7 of 11
YR4: Unit 4E – Modelling effects on screen
Lesson
Resources
Activity
4. Seeing Stars
Resources
Large display (see weekly plan) with
marker pens.
The class will record work on plain paper.
Main activity
Ask how we might draw a zigzag. Model with a pen on the board first.
Revision / oral
Look at the table from the last lesson.
Recap the polygon rule: divide 360 by the
number of sides to calculate the turtle turn.
Review computer work. What is the angle
to draw a 20-sided shape? A 15-sided
shape? Why did we avoid a heptagon?
(Logo will accept non-integral values, so
this could be drawn!)
What will happen if we make the left turn smaller? Try these:
Build on the polygon
rule by investigating
the construction of
stars.
One possibility is REPEAT 4 [FD 50 RT 90 FD 50 LT 90].
REPEAT 4 [FD 50 RT 90 FD 50 LT 45]
Key vocabulary
Factor
Multiple
Program
REPEAT 4 [FD 50 RT 150 FD 50 LT 105]
How many repeats will complete the star? How many points will it have? Draw attention to the
difference between the right and left turn: what do children notice? (It is 45 in each case.) Can they
suggest other 8-pointed stars?
NB:Show how to review and repeat previous commands. There is a 'How to...' sheet: see below.
Groups work on available computers. Individual’s work on paper: write programs for
different eight-pointed stars.
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YR4: Unit 4E – Modelling effects on screen
Lesson
Resources
Activity
Support
Give children a printed copy of the 'bent zigzags' above. 'Walk' them with a pencil. Write each move
the turtle makes, without using REPEAT. Discuss what is being repeated each time. Ask children to
draw what will happen if the turtle carries on repeating.
Challenge
Write programs for stars with six points, nine points.
Plenary
What is the rule for telling the turtle to draw an eight-pointed star? Six-pointed star? Nine-pointed
star? Can we suggest angles for other types of star? Test some of the children's suggestions.
Quick-fire questions: 'Eight-pointed star, right turn 130 degrees, left turn - what?'
Arrange times before the next lesson where all children can try their programs on the computer.
CEA@Islington - ICT Scheme of Work: p9 of 11
YR4: Unit 4E – Modelling effects on screen
Lesson
Resources
Activity
5. In a Spin
Large display (see weekly plan) with
marker pens. Group work following wholeclass introduction.
The main activity depends on computer
access, so is best run alongside other
work, as time permits.
Main activity
Show on the display how to define a procedure. Stress the benefit of using a short name that you'll
recognise! Refer to the ‘How to...’ sheet (see below), and have this available by the computers.
Create procedures.
Use them to make
'whirly' patterns.
Revision / oral
Recap the 'rules' for drawing regular
polygons and stars. What do we mean by
a regular shape? Quick-fire questions: Sixpointed star - right 150 degrees - left what?
Enter this, to check it's correct.
Key vocabulary
Procedure
TO
END
EDIT
Example:
TO HEX
>REPEAT 6 [FD 25 RT 60]
>END
Show that the computer now knows a new word:
CS HEX FD 25 HEX
and so on.
Show the class how to edit a procedure, e.g. to make the hexagon bigger.
EDIT "HEX
For now, simply say that the 'label' stops the computer trying to draw another hexagon!
Use the HEX command to draw a whirly pattern:
REPEAT 12 [HEX RT 30]
Why REPEAT 12? Why RT 30? Good revision of earlier work!
Children plan a whirly pattern based on their favourite polygon. Try this on the computer and print.
Record the Logo commands.
Extension
Do the same with your favourite star!
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YR4: Unit 4E – Modelling effects on screen
Lesson
Resources
Activity
Support
Give the children suggestions based on the simplest shapes and easily- remembered turns. Check
they fully understand 360 degrees as a whole turn.
Challenge
Once children have made patterns, ask them to write procedures to draw a rectangle and a
rhombus. It is a good idea to model on paper first. This is a good follow-up assessment activity.
Can they break down the problem?
Plenary
Children report on their work. Using the large display, show their patterns and talk about how they
were produced.
CEA@Islington - ICT Scheme of Work: p11 of 11
RESOURCE SHEET
Recording sheet
for Lesson 1
ICT Scheme of Work: Recording sheet for Lesson 1- p1 of 1
CEA@Islington
RESOURCE SHEET
Recording sheet
for Lesson 3
Turtling polygons
Name
square
Number of sides
4
Turn (degrees)
90
ICT Scheme of Work: Recording sheet for Lesson 3- p1 of 1
Total turn (degrees)
CEA@Islington
RESOURCE SHEET
How to enter
Logo commands
There must be a space between a command and the value:
For example:
FD
BK
RT
LT
PU
PD
PE
CS
FD 50
Forward
Back
Right
Left
Pen up
Pen down
Pen erase
Clear screen
e.g. FD 50
BK 28
RT 90
LT 270
REPEAT has a list of commands in square brackets:
For example:
REPEAT 4 [FD 50 RT 90]
Commands can be typed in lower case. You can put several commands on
one line, as long as they are all separated by spaces:
For example:
cs fd 20 rt 60 fd 40 pu
Press the up arrow to put old commands back on the command line. Press
Enter to do the commands again, or use the right and left arrows to make
changes.
Type PE then repeat the command by pressing the up arrow to delete
something you've just drawn. Don't forget to type PD before you draw
anything else!
ICT Scheme of Work: How to enter Logo commands - p1 of 1
CEA@Islington
RESOURCE SHEET
How to define and edit
a Logo procedure
To define a hexagon, type:
to hex
repeat 6 [fd 25 rt 60]
end
The commands appear like this:
Logo says, 'You defined hex.' Type hex to draw the hexagon.
Any name will do, but it's helpful to use a name that you'll
recognise later. Short names mean less typing!
To change the procedure, type:
edit "hex
The speech mark character is a label. It stops Logo trying to draw another
hexagon! You will see a new window:
Make changes, and then click End.
ICT Scheme of Work: How to define and edit a Logo procedure - p1 of 1
CEA@Islington
Write down the instructions to make the
Roamer draw the following shapes.
1.
2.
3.
4.
5.
6.
1.
2.
3.
4.
5.
6.
1.
2.
3.
4.
5.
6.
1.
2.
3.
4.
5.
6.
Write down the instructions to make the
Roamer draw the following shapes.
1.
2.
3.
4.
5.
6.
1.
2.
3.
4.
5.
6.
1.
2.
3.
4.
5.
6.
1.
2.
3.
4.
5.
6.
Try to program the Roamer to
draw this shape without taking the
pen up or going over the same line
twice.