SPIKE™ Prime Set

Keep It Safe

Use conditions to lock or unlock the door of a safe deposit box.

90-120 min.
Years 7-9 OR Key Stage 3

Lesson plan

1. Prepare

  • Read through the pupil material in the LEGO® Education SPIKE App.

2. Engage (5 Min.)

  • Use the ideas in the Ignite a Discussion section below to engage your pupils in a discussion relating to this lesson.
  • Use the video to explain the lesson.

3. Explore (20 Min.)

  • Have your pupils work in pairs to build the build the safe deposit box.
  • Ask them to play the program in order to see how the lock works.

4. Explain (5 Min.)

  • Facilitate a discussion about how adding conditions can make the safe deposit box even more secure.

5. Elaborate (15 Min.)

  • Ask your pupils to make their safe deposit boxes even more secure by adding more conditions to their programs.
  • Don't forget to leave some time for tidying up.

6. Evaluate

  • Give feedback on each pupil's performance.
  • In order to simplify the process, you can use the assessment rubrics that have been provided.

Ignite a Discussion

Start a discussion about iteration or fixing things by asking relevant questions. Here are some suggestions:

  • Can someone give an example of a safety device?
  • What makes a password strong or weak?
  • What's a condition?

Have your pupils watch this video to see what they're about to do.


Building Tips

Partner Build
Split each team's building tasks in order to ensure that everyone is actively involved.

  • Pupil A: Safe Deposit Box Door
  • Pupil B: Safe Deposit Box Box

Now we’re ready for the next lesson!
This model is also used as the base model for the next lesson, ‘Keep It Really Safe’. That's why there's a motor that isn't being used in this model. The motor's wire is clipped to the back of this version of the model.


Manual Unlock
This model has a manual key that can be used to unlock the door if needed.


Coding Tips

Main Program

SPIKE Kickstart your business Keep-it-safe Step03-Program - en-gb

Possible Solution

SPIKE Kickstart your business Keep-it-safe Teacher-Solution - en-gb

Other Programs

SPIKE Kickstart your business Keep-it-safe Teacher Other - en-gb


Simplify this lesson by:

  • Using the Dashboard to explain to your pupils how many degrees the motor has been turned. (You can find more information about the Dashboard in the Help Section of the SPIKE App.)

Take this lesson to the next level by:

  • Having your pupils modify the Light Matrix and sound file to customise their safe deposit box
  • Asking each team to modify their program and challenge another team to unlock their safe deposit box

Assessment Opportunities

Teacher Observation Checklist
Establish a scale that suits your needs, for example:

  1. Partially accomplished
  2. Fully accomplished
  3. Overachieved

Use the following success criteria to evaluate your pupils' progress:

  • The pupils understand what a condition is.
  • The pupils are able to use conditions in their program.
  • The pupils can discuss digital security in detail and with precision.


Have each pupil choose the brick that they feel best represents their performance.

  • Blue: I've used one condition in my program.
  • Yellow: I've used two conditions in my program.
  • Violet: I've used more than two conditions to create a super cool and safe program!

Encourage your pupils to provide feedback to one another by:

  • Having one pupil use the coloured brick scale above to score another pupil’s performance
  • Asking them to present constructive feedback to one another so that they can improve their group’s performance during the next lesson

Language Arts Extension

To incorporate the development of language arts skills:

  • Have your pupils explore the meaning of digital security terminology, like:

    ▷ Boolean
    ▷ Conditions
    ▷ Encryption
    ▷ Case-sensitive

Note: This will require additional time.

The pupils who enjoyed this lesson might be interested in exploring these career pathways:

  • Information Technology (Computer Programming)
  • Information Technology (IT Applications)
  • Information Technology (Oracle/Database Programming)
  • Information Technology (Web Design)

Teacher Support

The pupils will:

  • Explore conditional programming
  • Be able to explain the principles of digital security

LEGO® Education SPIKE Prime Set

CAS Computing Progression Pathways

Designs solutions (algorithms) that use repetition and two-way selection i.e. if, then and else. (AL)

Programming and Development:
Understands the difference between, and appropriately uses if and if, then and else statements. (AL)

Information Technology:
Recognises ethical issues surrounding the application of information technology beyond school.

Pupil Material

Student Worksheet

Download, view or share as an online HTML page or a printable PDF.