CompY9_3_Flowol .docx - Lady Lumley's School - · Web viewSince there is only a single digit on the Spaces indicator, ‘9’ is the maximum, but for testing purposes, any number up

LLS ICT Dept 2014-15 Year 8 - Computing

CompY9_3_Flowol

9_3 Overview for StudentsStudents learn about control systems using Flowol software. You will start by producing systems that use simple loops and basic outputs, and then move on to look at systems that have multiple inputs and outputs. They will refine their solutions using subroutines and variables.

Summary: The unit is a practical unit covering the principles of producing control and monitoring solutions using a flowchart-based interface (Flowol 4 or earlier). Pupils will start by producing systems that use simple loops and basic outputs, and then move on to look at systems that have multiple inputs and outputs. They will refine their solutions using subroutines and variables.

Learning Outcomes for the unit

At the end of this Unit all pupils should be able to:

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CompY9_3_Flowol • All - Identify everyday situations where computer control is used

• All - Identify common types of sensors used by control systems

• All - Identify control flowchart symbols and understand how they are used to break down problems

• All - Produce flowchart-based solutions for control systems that include sequences and loops

• All - Explain why control systems might fail and how this might impact on safety

. All - Produce control solutions for problems that include subroutines

Most pupils will be able to:• Most -Explain why control systems might fail and how this might impact on safety

. Most - Produce control solutions for problems that include subroutines

Some pupils will be able to:. Some - Produce control solutions for problems that include variables

Suggested Resources

Image manipulation software such as Paint Shop Pro (free), Gimp (free), Photoshop or Photoshop Elements.Worksheets 1 and 2

HML (100mins)LOs (BTEL)

Activities Home Learning and Portfolio Evidence

Teacher Notes

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Lesson 1 – Solving problems with flowcharts

●Identify control flowchart symbols and understand how they are used to describe systems.

●Develop a control flowchart solution for a simple problem.

Identify control flowchart symbols and understand how they are used to break down problems

Starter: Ask pupils to complete Flowol Worksheet 1 Zebra Crossing using the instructions provided on the worksheet or in the PowerPoint guide. After five minutes ask for volunteers to reveal the correct sequence at the front of the class.Outline the learning objectives for the lesson. Question pupils to assess any prior learning on programming (e.g. Logo, Small Basic, RoboMind, Kodu, Scratch, Python or GameMaker).Display the example flowcharts and ask pupils to explain what system the flowcharts describe. (A control system maintains the temperature of a room between 15oC and 20oC by turning a fan/heater on/off). Ask for suggestions about other systems that might work like this (e.g. greenhouse, central heating or air conditioning unit). Ask how the system ‘knows’ what the temperature is and draw out the idea of using sensors to monitor external conditions.Define each of the different flowchart symbols and explain how they are used to describe problems.Play the video Link Video Pedestrian Crossing 1948. Use the notes on this slide to give some background on the development of Zebra Crossings. Tell pupils that they are going to use the control software Flowol to produce a flowchart to control a modern zebra crossing. Demonstrate how to load Flowol and open the Zebra Crossing mimic. Discuss what symbols might be needed in the flowchart (e.g. START, PROCESS, DECISION and OUTPUT) and the steps needed (turn the lights on, pause, turn the lights off).Demonstrate how to add the START symbol and link it to an OUTPUT symbol with an arrow; note the output that turns the lights on/off. Add in a process to create a short delay of, say, 0.5 seconds. Add a STOP symbol and ask pupils if this is appropriate for the zebra crossing, drawing out the idea that a continuous loop is needed. Show how to achieve this by linking the output symbol back to the START symbol.Play the video of the Zebra Crossing Mimic, which shows the Zebra Crossing mimic solution running in Flowol. This enables you to demonstrate the end result without showing the solution in Flowol. The Flowol solution is saved in the folder as Solution Zebra. Ask pupils to create their solution and stress that the lights must flash as seen in the video. Circulate and support pupils getting them to check this and modify the length of their delays if necessary.

HomeworkStudy traffic light sequences as preparation for next lesson.

PowerPoint presentation Flowol L1 Flowcharts.pptxFlowol Worksheet 1 Zebra Crossing

Link Video Pedestrian Crossing 1948

Flowol 4 (or earlier) with the Zebra Crossing mimic open

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Identify everyday situations where computer control is used

---------------------------Lesson 2 - Sequence

●Understand why a control system might fail and explain the impact this can have on safety

Display and briefly review the zebra crossing flowchart (most pupils will be able to solve this relatively quickly and successfully).Show Mimic Video Crossing Patrol. Ask pupils to move on to this mimic and produce a solution that matches this outcome.Briefly review the Crossing flowchart (Solution Crossing Patrol) and ask pupils if they all achieved the same solution. Demonstrate how to combine more than one operation within the same process in order to improve efficiency and reduce the number of symbols.

Plenary: Ask pupils to discuss in groups examples of other real life situations where computer control is used. Gather responses, recording them on the whiteboard.Refer to the examples on the whiteboard and pick out traffic lights (if pupils did not suggest this, add it and note that this is a very common control system that they overlooked in their discussions). Tell pupils that next lesson they will work on producing a control solution for traffic lights.---------------------------------------------------------------------------------------------------

Starter:Display Link Video Traffic Light Malfu

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PowerPoint Guide: Flowol L2 Controlling Traffic LightsLink Video Traffic Light Malfunction

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●Develop a control solution for a system that uses two flowcharts operating in sequence

Explain why control systems might fail and how this might impact on safety

Produce flowchart-based solutions for control systems that include sequences and loops

nction which can also be found at: http://www.youtube.com/watch?v=O6H9ywJ2CkoDirect pupils into small groups and ask them to discuss what is happening. After 2-3 minutes ask

Video Traffic Light SequencesFlowol Worksheet 2 Traffic Light Sequences

Flowol 4 with Bridge Lights mimic file openedMimic Video Bridge 1

Solution Bridge Light 1

Mimic Video Bridge 2Solution Bridge Light 2

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Lesson 3 - Sensors

●Identify common types of sensors used in control systems

●Use decision symbols in a flowchart

●Develop a control solution for a system that uses multiple sensors

Identify common types of sensors used by control systems

for responses, drawing out the idea that the system controlling the lights has developed a fault. Discuss what might have caused this (e.g. water has got into the hardware, some of the

PowerPoint Guide: Flowol L3 Sensors

Link Video Home Automation

Worksheet 3 Automation Tasks

Flowol 4 with the Automatic Home mimic open

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hardware has broken down). What are the implications of a failure in a control system? Where are other control systems used, and what would be the consequences of a malfunction

Doorbell

Solution Automatic Home

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---------------------------

Lesson 4 - Subroutines

●Develop a control solution for a system that

in these? E.g. Aircraft ‘fly-by-wire’ systems or patient monitoring systems.Use Video Traffic Light Sequences and Flowol Worksheet 2 Traffic Light Sequences to highli

Homework suggestion: Research what a subroutine is and how one might be used – there is a useful PDF manual available on the Flowol website that would help them here.

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Flowol Worksheet 3b Greenhouse TasksSolution GreenhouseLink Video Hydroponic Lettuce Factory

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vPowerPoint Guide:

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includes a subroutine

● Understand how the use of subroutines can make programs more efficient

Produce control solutions for problems that include subroutines

ght the pattern in traffic light sequences. Give pupils time to complete the two light sequence tables by watching the video and discussing the answers. Question pupils to ensure that

Flowol L4 SubroutinesVideo Pelican Crossing (Pedestrians) – 1969

Video Pelican Crossing (Motorists) - 1969Flowol Worksheet 4 Pelican CrossingFlowol Worksheet 4 Pelican Crossing

Flowol 4 with the Pelican Crossing mimic opened

Solution Pelican 1

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they all have a correct set of steps before moving on. This activity could be done in small groups or as individuals.Remind pupils how to load Flowol and open the Bridg

Solution Lighthouse Subroutine

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e Lights mimic. Question pupils to identify the symbols needed in the flowchart (e.g. START, PROCESS, DECISION and OUTPUT. Demonstrate the outputs that turn the lights

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Lesson 5 - Actuators

●Understand what an actuator is used for in a control system

●Understand what a variable is and explain how variables can be used to help control systems● Develop a

control solution for a systeProduce control solutions for problems that include variables

●m that uses actuators and variables

on/off. Explain that flowchart symbols should only flow from top to bottom and left to right. Pupils should end up with a long chain of symbols with a loop arrow.Ask pupils to create a flowch

PowerPoint Guide: Flowol L5 ActuatorsLink Video Car Park

Flowol 4 with the 3D Car Park Barrier mimic open

Flowol Worksheet 5 Car ParkFlowol Worksheet 5 CompletedFlowol 4 with the 3D

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●art to control the lights on the near side of the bridge. Stress that the lights must operate in the same way with delays as listed in Table 2 on their worksheet. Circulate and support pupils

Car Park Barrier

Solution Car Park Entry.flo

Solution Car Park Exit.flo

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as they work. Show the Mimic Video Bridge Light 1. This enables you to demonstrate the correct outcome without displaying the solution. (Shown in Solution Bridge

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Light 1.)As pupils successfully complete their flowchart, move them on to an extension activity to create a second flowchart alongside the first to control the lights on the opposite

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side of the bridge. Circulate and support pupils as they work. Mimic Video Bridge Light 2 shows a looped video of the full solution and can be displayed at this point

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if required.Open the full solution flowchart Solution Bridge Light 2 in Flowol and use it to assess pupil progress. Ask pupils: How does your solution compare to this

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one? How is your solution different? Which solution is better and why? Which parts of the solution did you find easy and why? Which parts of the solution did you find harder and why?Questi

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on pupils to identify the potential shortcomings of this system (e.g. it is timed and can’t respond to traffic flow) and ask how it could be improved (e.g. use sensors to detect approachin

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g cars and adapt to changing traffic volumes or times of day or year). Note how the two flowcharts in Solution Bridge Light 2 need to be exactly synchronised.If time permits, the

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video Link Video LA Gridlock shows how control systems are used in a large and complex traffic system in Los Angeles to synchronise every light in the city with each other. This can

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also be found at: http://www.today.com/video/today/51414149#51414149.

Starter:What could you use a computer to control inside your home?discuss the question and come up with suggestions. After five minutes, question pupils, gathering responses and recording them on the whiteboard.You can show the video of sensors and control.Outline the learning objectives for the lesson linking back to the work already completed during the previous lesson on subroutines.Explain that a sensor is used to take readings to detect a change in its environment. Ask pupils to identify different types of sensor and their uses.Load Flowol and open the of sensor used in this system (e.g. light, heat and movement) and what they are needed for (e.g. controlling the lights, maintaining the temperature and controlling the security light). Note how the temperature and sunlight levels can be adjusted using the control panel on the right or by using the left and right mouse buttons. In this situation we are detecting real values.

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Explain to pupils how a decision symbol works and how to implement one in a flowchart using a yes and no arrow rather than a standard arrow. The Lighthouse mimic would provide a useful demonstration to turn on the lighthouse in response to a drop in sunlight.Describe the parts of the Automatic Home mimic and ask pupils to complete the tasks on Worksheet 3 Automation Tasks:

1. Turn the living room 2. Turn the living room 3. Turn the living room 4. Ring the Doorbell.wav5. Turn the garage door sensor6. Open the garage door when the close button

Check that pupils understand the task requirements before they start work. Solutions to all six tasks are given in the flowchart file home.floAsk pupils to start by creating two flowcharts that will control the fan and the fire heater in the living room (work.Tell pupils ready to start done as follows and can be simulated on the mimic by pressing the red switches which control the door, or manually to by using a two clicks of the left or right mouse buttons.

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Some extension pupils could be shown how to include a subroutine to solve the problem rather than a single flowchart.Extension:Pupils who complete every task can extend their solution to open and close the living room blinds depending on the outside light level.For further extension work, pupils can work on the Worksheet 3b Greenhouse TasksSolution Greenhouselesson following this one as an activity for some pupils if others need more time to finish their automated home solution.Link Videocan be found at:useful background context for this.Homework suggestion:there is a useful PDF manual available on the Flowol website that would help them here.

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-----------------------------------------------------------------------------------------------Starter:Show Video Pelican Crossing (Pedestrians) – 1969.Explain that this clip is a public information film from 1969

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when these crossings were first introduced.Trivia! You could note here that Puffin crossings are more common now. The Puffin crossing (Pedestrian User Friendly Intellig

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ent Crossing) was developed to replace the Pelican crossing. Puffin crossings differ from Pelican crossings as they do not have the flashing green man and flashing amber signal. The

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red and green man are located just above the push button on the same side as the pedestrian and this encourages pedestrians to face the oncoming traffic while waiting for the green man

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to show.Ask what is the ‘default setting’ for this control system (red man on, green lights on) and what triggers this to ‘change state’ (the button being pressed – draw

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out the idea that the system is constantly checking to see if the button has been pressed). Explain the term ‘default’.Outline the learning objectives for the lesson linking back

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to the work already completed in previous lessons.Play Video Pelican Crossing (Motorists) – 1969. Pupils can complete Worksheet 4 Pelican Crossing at this point if it would

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help them.Ask pupils to load Flowol and open the Pelican Crossing mimic.Pupils should find the basics of this mimic (without flashing lights) straightforward and be able to add

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in a decision at the start to check whether the wait button has been pressed. The rest of the sequence will be similar to the traffic lights in the Bridge Light mimic in lesson 2.Allow pupils

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time to consolidate their learning so far to create the flowchart for the mimic as described, without the flashing lights. They will later add in the flashing light sequence as a subroutine.

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Subroutines:Explain that the first step in solving the flashing light problem will be to create a separate flowchart called a subroutine to control the flashing amber lights and

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green man.Explain to pupils what a subroutine is and that the flash subroutine only needs to make the lights flash once. The ‘Flash’ subroutine can then be repeated or ‘called’ three

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or four times to create multiple flashes without writing any extra instructions. This is more efficient.In order to show how a subroutine is written and called, open Solution

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Lighthouse Subroutine. When the sun is off, i.e. it is dark, the lighthouse lamp flashes continuously and the lights in the lighthouse go on.Demonstrate how to create a subro

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utine using the Lighthouse mimic to make the lamp flash when it is dark (i.e. when the sun is off). In this example, the advantages of using a subroutine are not so obvious and the

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code could all be in the main program.

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Refer pupils back to the flowchart they

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created in Lesson 1 to make the Zebra Crossing lights flash (Solution Zebra Crossing can be used to demonstrate this if required). Ask pupils how this solution could be rewrit

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ten with a subroutine making the lights flash.Use the Pelican mimic to:

● I

● O

●

● P

● D

Explain that this approach to programming using

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subroutines or small sub-programs is referred to as ‘modular’. This is a commonly used approach that helps to break down large and very complex problems into

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smaller parts that separate teams of programmers can work on. Tell pupils that this is how computer games are developed. Illustrate this idea by displaying Link Video How video

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games are made which can also be found at: http://www.youtube.com/watch?v=u0FoYgZmlMs

Starter:Introduce the lesson by playing a light-hearted video of a car park barrier prank, Link Video Car Parkcould be causing the problems if they were real. Question pupils to draw out the

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key ideas that real problems could be due to faulty sensors, poor programing or hardware failure.Tell pupils that this lesson will focus on producing their own solutions to control a car park barrier more successfully than the example they have just watched.Load Flowol and open the from Flowol as a supplementary download called 3D Mimics. See: http://www.flowol.com/Secondary3DMimicPack1.aspx)Remind pupils about the automated home system in the Lesson 3 and the sensors that it used. Ask pupils to suggest what type of sensor is being used in this system (pressure pads in the road) and what the sensors are needed for (e.g. to detect cars and raise/lower the barriers safely). Point out the motors and introduce the term actuatorsensors in control systems.Discuss how Google’s driverless car might use sensors and actuators to detect other road users and traffic signals, and to control acceleration and braking. Video Google’s Self Driving CarDistribute complete the Input and Output tables.Demonstrate how to use the motors in Flowol using the Automatic Home mimic to open and close the garage door.

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Review the planning sections of their worksheets. Clear up any misconceptions (the use of a delay to allow time to fully raise or lower the door, or car park barrier, is often a point that is missed at this stage) and then tell pupils to start creating their flowcharts for the entry and exit of the car park. Tell them that they need to start by creating two subroutine flowcharts for the entry barrier: one to raise it and another to lower it. These subroutines will then need to be combined in a main flowchart. Tell pupils they will deal with the car park sign later.

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Solution Car Park Entry the flowcharts are covered by the mimic image.Pupils who complete the entry flowcharts can create two more subroutine flowcharts: one to raise the exit barrier when a car is ready to leave the car park; and another to lower the exit barrier once the car has passed through the exit barrier. These subroutines then need to be combined in a main flowchart that deals with cars leaving the car park. Solution Car Park Exit provides a demonstration of this. Encourage more able pupils to consider more efficient

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approaches at this stage such as copying and pasting their entry flowcharts and editing them to produce this part of the system.Variables:Introduce variables to the class and explain that a variable is a named area of memory which can store a value. This value can be changed by a program and the program can use decision symbols to make choices based on the value of a variable.Show pupils how a variable can be used in Flowol using the examples in the PowerPoint guide.Flowol automatically gives two variables called x and y. These can be given more meaningful names, e.g. Speed or Spaces, rather than x or y. Flowol can use decisions to check the number of spaces left, and when Spaces = 0, it can display the ‘FULL’ sign.Ask pupils how they might use a variable in the Car Park mimic.Point out in Flowol how to edit a variable name by clicking the “I” symbol to the right of the variable name. Then tell pupils to modify their flowcharts to turn on the ‘FULL’ sign when the number of spaces reaches 0.They will need a simple decision flowchart to turn on the sign if Spaces = 0:

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They will also need to add in symbols to initialise the variable, add or subtract 1 to the variable depending on whether the car is entering or exiting the car park, and add in a decision to prevent the barrier from opening if the car park is full.Starter:Introduce the lesson by playing a light-hearted video of a car park barrier prank, Link Video Car Parkcould be causing the problems if they were real. Question pupils to draw out the key ideas that real problems could be due to faulty sensors, poor programing or hardware failure.Tell pupils that this lesson will focus on producing their own solutions to control a car park barrier more successfully than the example they have just watched.Load Flowol and open the from Flowol as a supplementary download called 3D Mimics. See: http://www.flowol.com/Secondary3DMimicPack1.aspx)Remind pupils about the automated home system in the Lesson 3 and the sensors that it used. Ask pupils to suggest what type of sensor is being used in this system (pressure pads in the road) and what the sensors are needed for (e.g. to detect

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cars and raise/lower the barriers safely). Point out the motors and introduce the term actuatorsensors in control systems.Discuss how Google’s driverless car might use sensors and actuators to detect other road users and traffic signals, and to control acceleration and braking. Video Google’s Self Driving CarDistribute complete the Input and Output tables.Demonstrate how to use the motors in Flowol using the Automatic Home mimic to open and close the garage door.

Review the planning sections of their worksheets. Clear up any misconceptions (the use of a delay to allow time to fully raise or lower the door, or car park barrier,

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is often a point that is missed at this stage) and then tell pupils to start creating their flowcharts for the entry and exit of the car park. Tell them that they need to start by creating two subroutine flowcharts for the entry barrier: one to raise it and another to lower it. These subroutines will then need to be combined in a main flowchart. Tell pupils they will deal with the car park sign later.

Solution Car Park Entry the flowcharts are covered by the mimic image.

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Pupils who complete the entry flowcharts can create two more subroutine flowcharts: one to raise the exit barrier when a car is ready to leave the car park; and another to lower the exit barrier once the car has passed through the exit barrier. These subroutines then need to be combined in a main flowchart that deals with cars leaving the car park. Solution Car Park Exit provides a demonstration of this. Encourage more able pupils to consider more efficient approaches at this stage such as copying and pasting their entry flowcharts and editing them to produce this part of the system.Variables:Introduce variables to the class and explain that a variable is a named area of memory which can store a value. This value can be changed by a program and the program can use decision symbols to make choices based on the value of a variable.Show pupils how a variable can be used in Flowol using the examples in the PowerPoint guide.Flowol automatically gives two variables called x and y. These can be given more meaningful names, e.g. Speed or Spaces, rather than x or y. Flowol can use decisions to check the number of spaces left, and when Spaces = 0, it can display the ‘FULL’ sign.Ask pupils how they might use a variable in the Car Park mimic.Point out in Flowol how to edit a variable name by clicking the “I” symbol to the right of the variable name. Then tell pupils to modify their flowcharts to turn on the ‘FULL’ sign when the number of spaces reaches 0.They will need a simple decision flowchart to turn on the sign if Spaces = 0:

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They will also need to add in symbols to initialise the variable, add or subtract 1 to the variable depending on whether the car is entering or exiting the car park, and add in a decision to prevent the barrier from opening if the car park is full.

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Lessons 6 - Variables and Assessement

● Understand how a digital 7-segment display works

● Implement the 7-segment display

●Complete the assessment portfolio

Remind pupils of the use of variables to monitor the number of cars or spaces that are inside the car park. Open the Car Park mimic with the Solution Car Park Complete and hide the seven-segment display flowchart behind the mimic image.Ask how many spaces this car park has. How does the system ‘know’ how many cars are in the car park? Draw out the idea that the system must be counting spaces remaining as cars come in and go out of the car park.Highlight the car park display in the mimic and discuss how they might get this to light up with the correct number. Run the solution to demonstrate the finished program. Show pupils how the decision symbol could be used to check the value of the ‘Spaces’ variable and act accordingly.Ask pupils to ensure that they have a system which will turn on the ‘FULL’ sign if the car park is full. Discuss what the class think is the maximum number of cars in the car park. Since there is only a single digit on the Spaces indicator, ‘9’ is the maximum, but for testing purposes, any number up to nine is fine.Show pupils the 7-segment display and distribute Flowol Worksheet 6 Display and ask pupils to plan the outputs in the 7-segment display. Circulate and support pupils as they work, moving them on to create the subroutine and integrate into the main flowchart when ready. A completed version of the worksheet is also available.

PowerPoint Guide: Flowol L6 VariablesSolution Car Park Complete.flo

Flowol Worksheet 6 Spaces DisplayFlowol Worksheet 6 Spaces Display Completed

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Question the group to assess progress. Ask pupils: How much of the solution did you complete? Which parts of the solution did you find easy and why? Which parts of the solution did you find hard and why?AssessmentAsk pupils to complete the assessment portfolio (found in the root folder for this unit). A screenshot of their most advanced program should be included. Pupils may like to use Alt+PrtScrn to take a screenshot of just the active window rather than PrtScrn alone which will capture the entire screen.The Assessment Portfolio could be uploaded to an area on a VLE such as Moodle, Frog or Fronter for marking. Flowol

Assessment Portfolio (in root folder)

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Solution Lighthouse (Assessment question).flo

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Documents

CompY9_3_Flowol .docx - Lady Lumley's School - · Web viewSince there is only a single digit on the Spaces indicator, ‘9’ is the maximum, but for testing purposes, any number up