What students build
- A space map with three or more destinations
- A controllable taxi
- Arrival detection at each destination
- Passenger pickup and delivery states
- A completed-trip counter
- A reset path after mistakes
Computer Lab Project
Computer Lab ProjectGrandma's Intergalactic Taxi
Grandma drives a taxi in space and has no intention of missing another pickup. Read the map, collect passengers, and deliver them to the right coordinates.
Project brief
What students learn
- Coordinates
- Movement
- Distance
- Sequences
- Score
- Boundaries
- Debugging
What students need
- Browser
- Scratch editor
- Keyboard
Computer Lab brief
The required systems set the finish line. Students choose the map and controls, then decide how the taxi detects arrivals and handles dispatches.
Required systems
What must exist.
- A space map with three or more destinations
- A controllable taxi
- Arrival detection at each destination
- Passenger pickup and delivery states
- A completed-trip counter
- A reset path after mistakes
Suggested build order
One useful route through the problem.
- Draw the map and write down the coordinates of each destination.
- Give the taxi a fixed starting position and add movement controls.
- Make arrival work at one station, then add the others.
- Create separate pickup and delivery states for one passenger.
- Count a completed trip once, then reset the current request.
- Try the map boundaries, wrong destinations, and repeated arrivals.
Checkpoints
- 1The taxi always starts from the chosen coordinates.
- 2At least three destinations have distinct locations.
- 3Pickup and delivery are different states.
- 4One delivery adds exactly one trip.
- 5The student can explain one route using x and y changes.
Challenge cards
Choose one, combine compatible cards, or propose an equivalent challenge.
Fuel decreases with movement.
Passenger destinations are randomized.
A wrong station costs time.
An asteroid zone changes the route.
Coordinates appear as a navigation display.
Create a shortest-route challenge.
Test questions
- Does the taxi always start at the chosen coordinates?
- Can it arrive at all three destinations?
- Can a passenger be delivered before being collected?
- Does one delivery add exactly one trip?
- What happens after a wrong destination or route?
Common mistakes
- Testing only the easiest successful path.
- Changing several systems before retesting.
- Resetting only part of the project state.
Challenge levels
Builder
Complete and explain the required systems.
Inventor
Choose one challenge card and test the result.
Boss Level
Make the dispatcher give coordinates instead of flashing the destination: 'Pickup requested near x: 140, y: -80.' The player must read the request and navigate there.
What to demonstrate
- Three destinations on a coordinate map
- A complete pickup and delivery
- A trip counter that changes once per delivery
- Recovery from a wrong route or mistake
- One independently chosen challenge card