Grand Challenge

Bring it all together

Year 7 Computer Science — Synthesis

The Challenge

Write an algorithm to navigate from START to EXIT through the maze.

📏 Max 20 lines — including lines inside loops

🔁 Must use at least one REPEAT loop

❓ Must use at least one IF/ELSE

🤖 Must be peer-testable — another pair will follow it as a robot

Study the Maze

Find the route from A1 to H8
Where do you repeat the same move? → Use a loop
Where do you face a decision? → Use IF/ELSE
What variables do you need to track?

Mark your planned route on the planning sketch. Then write!

Write Your Algorithm

Use proper notation:

REPEAT 4 TIMES { move right }
IF key = True:
    enter gate
ELSE:
    find alternate route

Count your lines! Stay within 20.

SWAP!

Peer Testing

Give your sheet to another pair. They are your robots.

Follow the algorithm EXACTLY on the maze grid
Record where it succeeds and where it fails
Fill in the Peer Test section

Feedback & Revision

Get your sheet back. Read the peer test results.

What failed?
Was the bug a wrong-order, missing step, or logic error?
Fix the minimum — don't rewrite the whole thing

Write your fix in the Author's Response section.

Reflection

Which was harder: writing the algorithm or testing someone else's?
Why is peer review valuable?
Could you solve this in 10 lines? What would need to change?
Where did loops and conditionals make your solution more efficient?

Key Takeaway

Real programs combine all concepts — algorithms, variables, loops, and conditionals work together.

Writing correct, efficient solutions requires planning, testing, and revision.

That's software development.