← ACARA Digital Technologies Years 5–6

Locking a device screen

A lock that needs a passcode, passphrase or fingerprint to open your device, so other people cannot use it when you walk away from it.

Part of: ACARA Digital Technologies Years 5–6 — Staying Safe Online — Module 18

Understanding Locking a device screen in ACARA Digital Technologies Years 5–6

What it does: Locking when you leave stops someone else from using your device while you are gone. A passcode only protects your device if you keep it private, so you do not share it. A screen lock only opens for the right passcode, passphrase or fingerprint. Fingerprint and face unlock use something that is just yours, so other people cannot easily open your device. Easy passcodes like 1234 are some of the first things people try. Pick one that is harder to guess. An unlocked device can show your personal data and let others use your accounts.

Common mistakes: A passcode must stay private. Telling a friend means they could unlock your tablet. It should say to keep my passcode secret. If the lock time is never, the screen will not lock by itself and anyone can use the device. It should be a short time, like 30 seconds.

Class: _____________________  ·  Name: _____________________  ·  Date: _________

Free printable worksheet with full answer key — or add this module to a class and your students practise it interactively.

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This module's key terms are also in a printable crossword (Modules 137–153) and word search (Modules 137–225).

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Learning
Duo
You put your tablet down to get a snack. What should you do first?
Lock the screen so no one else can use itLeave it open so it is ready when you get back
Matches
passcode = "1234" share(passcode, "friend")
↓
The passcode is shared with a friend. A screen lock only works if the passcode stays private, so do not share it.
Applying
Meanings
Term
screen lock
Meaning
A lock that needs a passcode, passphrase or fingerprint to open your device, so other people cannot use it when you walk away from it.
Practice
IF I walk away from my device THEN
Testing
Gaps
()
Check Answer
Spots
2 press the lock button
3 tell my mate my passcode

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Quick Questions

1. You put your tablet down to get a snack. What should you do first?
A. Leave it open so it is ready when you get back
B. Lock the screen so no one else can use it ✓
A screen lock stops other people from using your device when you walk away from it.
2. Which statement about a screen lock is true?
A. It needs a passcode, passphrase or fingerprint to open the device ✓
B. It lets anyone open the device by tapping the screen
A screen lock only opens for the right passcode, passphrase or fingerprint.
3. Your friend asks for your passcode so they can play a game on your phone. What is the safe choice?
A. Keep your passcode private and say no politely ✓
B. Tell them, because they are your friend
A passcode you do not share keeps your device and your accounts safe. Only share it with a trusted adult like a parent or carer if they need to help.
4. Which one is a screen lock that uses your body?
A. Wallpaper picture
B. Fingerprint or face unlock ✓
Fingerprint and face unlock use something that is just yours, so other people cannot easily open your device.
5. Which passcode is the better choice for a screen lock?
A. A passcode that is hard to guess and that you keep to yourself ✓
B. 1234 because it is easy to remember
Easy passcodes like 1234 are some of the first things people try. Pick one that is harder to guess.

Match the Pairs

screen lock → A lock that needs a passcode, passphrase or fingerprint to open your device, so other people cannot use it when you walk away.
fingerprint unlock → Opens your device by checking your own fingerprint, so only you can get in.
Lock your screen as soon as you walk away from your device → lock_screen() # before leaving the desk
Keep your passcode secret and do not share it with friends → passcode = "private"
passcode = "1234" share(passcode, "friend") → The passcode is shared with a friend. A screen lock only works if the passcode stays private, so do not share it.
leave_desk() lock_screen() → The screen is locked after leaving the desk. It should be locked before you walk away, or someone could use the device first.

Key Term

screen lock
A lock that needs a passcode, passphrase or fingerprint to open your device, so other people cannot use it when you walk away from it.

Fill in the Blanks

1. IF walkingAway THEN lockScreen() END IF
Hint: Type the command that locks your screen when you leave your device, written as one camelCase word.
2. IF friendAsksForPasscode THEN sharePasscode ← FALSE
Hint: Type the true or false value that shows your passcode is kept private.
3. IF fingerprintMatches THEN unlockDevice() ELSE keepLocked()
Hint: Type the keyword that says what to do when the fingerprint does not match.
4. IF fingerprintMatches OR faceMatches THEN unlockDevice()
Hint: Type the logic word that lets either unlock method open the device.
5. IF typedCode = savedPasscode THEN unlockDevice() ELSE keepLocked()
Hint: Type the symbol that checks whether the typed code is equal to the saved passcode.

Spot the Error

Question 1
A IF I leave my tablet
B press the lock button
C tell my mate my passcode
D END IF
Line C — A passcode must stay private. Telling a friend means they could unlock your tablet. It should say to keep my passcode secret.
Question 2
A SET unlock TO fingerprint
B SET lock_time TO never
C IF screen idle for lock_time
D lock the screen
Line B — If the lock time is never, the screen will not lock by itself and anyone can use the device. It should be a short time, like 30 seconds.
Question 3
A SET passcode TO my birthday
B SHOW passcode to nobody
C LOCK screen WITH passcode
Line A — A birthday is easy for other people to guess. The passcode should be hard to guess.
Question 4
A SET unlock TO face_or_finger
B IF face matches owner
C unlock the phone
D ELSE unlock the phone anyway
Line D — If the face does not match the owner, the phone must stay locked. Unlocking it anyway defeats the screen lock.
Question 5
A IF I finish using my laptop
B close the lid or press lock
C screen stays open for anyone
D END IF
Line C — A screen lock should ask for the passcode so other people cannot use the laptop. It should not stay open for anyone.

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