Smart Safe-Lesson Slides

Year 3 Lesson 9

Smart Safe

Warm-Up What’s an algorithm?

Step-by-step instructions to write and follow, in order to solve a given problem.

Warm-Up Effective Instructions In pairs, number yourselves 1 and 2.

Number 1’s must leave the room!

Warm-Up Effective Instructions Number 2’s: you have 1 minute to memorise this sketch of a safe!

Next you will have to give instructions to your partner.

Warm-Up Number 1’s come back in!

Number 2’s: Can you give clear, concise instructions to your partner?

1

Give verbal instructions

2

Now give written instructions

Warm-Up Share your sketches: How did you do?

Number 1’s: What was effective or ineffective about the instructions you were given?

Which worked better – verbal or written instructions?

Warm-Up Inputs and Outputs The instructions were the input into Number 2s’ brains.

The output was their sketch.

The brain processed the information like a computer.

Understanding this process means you have algorithmic thinking!

Mini-lesson Can you identify features of an effective safe?

An ‘If-Then’ statement can help make safes more effective. For example: If the safe is closed, then the light shines yellow.

If the safe is open, then the light shines red.

Mini-lesson What have inputs and outputs got to do with safes?

An input is the value taken into a system to be processed.

An output is the data or information generated.

Having an alert on the safe would be an output.

What would be the input?

Keywords Complete the keyword activity in your Student Handout: If-Then

Output Safe

Input

Algorithm

Let’s Discuss 1. Which block could be used as an input in the system in order to make the safe ‘smart’? a. The Button block b. The Light Sensor block c. The DC Motor block

Let’s Discuss 1. Which block could be used as an input in the system in order to make the safe ‘smart’? b. The Light Sensor block

2. With a partner, discuss how you could build a system that would alert the user when their safe has been opened.

Let’s Build!

Create an alarm system for your ‘safe’ 1

Compare: set to ‘> 30’

Compare: set to ‘< 29’

Colour: set to Red

Colour: set to Yellow

Let’s Build!

Create an alarm system for your ‘safe’ 2

Test your system!

What will happen when there is an intruder?

RGB LED

Light Sensor

Challenge 1 Create a smart safe that has a sound alert to confirm that the alarm is on standby.

Additional Compare: ‘> 3’

Sound Player: Alarm sound

Checks for Understanding 1. What is an algorithm? a. A process, or set of instructions, to be followed in order to solve a problem. b. Instructions to end a system only. c. Multiple options for solving a problem.

2. What does the symbol > mean? a. Greater than or equal to b. Less than or equal to c. Greater than

Checks for Understanding 1. What is an algorithm? a. A process, or set of rules, to be followed in order to solve a problem.

2. What does the symbol > mean? c. Greater than

Debug It!

How can I make the alert more effective when the â&#x20AC;&#x2DC;safeâ&#x20AC;&#x2122; is opened?

Debug It! How can I make the alert more effective when the ‘safe’ is opened?

Interval: ‘3 seconds’ Virtual Buzzer:

low volume

Challenge 2 Create an image-capture feature in the system to photograph the intruder additional Interval: â&#x20AC;&#x2DC;500 millisecondsâ&#x20AC;&#x2122;

What are the advantages and disadvantages of using a camera?

Camera

Challenge 2 Can you use these words to discuss your system?

event (input) action (output) If â&#x20AC;Ś then â&#x20AC;Ś Record in your Student Handout

Checks for Understanding 1. What is the impact of the Interval block on the Camera block? a. A single image is captured at the same time as the red light. b. Images are captured at the same time as the yellow light. c. Images are captured at set intervals.

2. What is one reason why a safe needs to be carefully designed? a. To ensure it can be opened by anyone. b. To ensure the correct action happens. c. To ensure it is locked at all times.

Checks for Understanding 1. What is the impact of the Interval block on the Camera block? c. Images are captured at set intervals.

2. What is one reason why a safe needs to be carefully designed? b. To ensure the correct action happens.

Chilli Challenges

Experiment with creating a light that flashes on and off. Can you create a system where the light flashes quicker than the sound plays?

Experiment with adding a reset feature after the alarm has been triggered. Can you use the Key Press and Text blocks into the system?

Hint: Enter ‘reset’ in the Text block.

Experiment with adding a timer so the alarm is only active during a set time period. Can you add a Time Trigger block into the system?

Exit Ticket What have you learned today?

Can you annotate your system?

Exit Ticket Now letâ&#x20AC;&#x2122;s apply what you know!

How do you think these safes are kept secure?

How do you think you would open one of these safes?