What students build
- A grid-like map
- Clear movement commands
- A known start
- A target route
- Command feedback
- Reset behaviour
Guided Class Project
Guided Class ProjectRobot Hamster Command Centre
Program a robot hamster to patrol snack storage without treating every crumb as an international emergency.
Visible system / hidden curriculum
Build something clear enough to test.
What students learn
- Events as triggers
- Command order
- Position and direction
- Messages between scripts
- Prediction
- Sequence debugging
What students need
- Browser
- Scratch editor
- Keyboard
- Student-drawn hamster and map
This is a game about robot logic. It does not require physical robot hardware.
Suggested build order
Decisions and checkpoints, not a wall of copied blocks.
Students may use different artwork and implementation details. The shared structure keeps the concept teachable.
- 01
Create the command map
Task: Draw a simple route with a start, target, and one obstacle.
Build and test this part before adding the next system.
- Checkpoint
- The route can be described in steps.
- Likely mistake
- Making the grid too small for the sprite.
- 02
Define movement commands
Task: Connect keys or buttons to forward and turn actions.
Build and test this part before adding the next system.
- Checkpoint
- Each command has one clear effect.
- Likely mistake
- Mixing position and direction changes.
- 03
Set a known start
Task: Reset position and direction together.
Build and test this part before adding the next system.
- Checkpoint
- Every attempt begins identically.
- Likely mistake
- Resetting position but not direction.
- 04
Run a sequence
Task: Trigger several commands in order with visible pacing.
Build and test this part before adding the next system.
- Checkpoint
- The hamster reaches a predictable result.
- Likely mistake
- Commands overlap because there is no timing.
- 05
Report success or collision
Task: Use sensing and messages to explain the outcome.
Build and test this part before adding the next system.
- Checkpoint
- The project distinguishes target and obstacle.
- Likely mistake
- The result message appears before movement ends.
Test it
Try the edges, not only the easy success.
- Does each command do one thing?
- Does order matter visibly?
- Does reset restore direction?
- Can a route collide between grid points?
- Does the result wait for the sequence?
Common mistakes
Read the clues before changing code.
- No event starts the command sequence.
- Turns also move the hamster.
- Direction is lost after reset.
- Several key events run at once.
Improve it
Preserve the core system while changing the project.
- Add a second route.
- Display the command history.
- Allow command planning before execution.
- Create reusable route functions.
Challenge levels
Choose meaningful difficulty.
Builder
Complete a five-command route.
Inventor
Store a planned command sequence before running it.
Boss Level
Create reusable command procedures for common turns.
Show-teacher checkpoint
Demonstrate the working decisions.
- Known start and direction
- Three distinct commands
- A complete route
- Obstacle response
- Visible command feedback
- One sequence repair