Debug the Drawing

The robot does the drawing exactly — not what you meant. Read each program like a robot would. One step is wrong. Find it, then trace where the robot really ends up.

How to read the moves:

• ↑ Forward N — drive straight N squares the way the robot is facing
• ↻ Turn right / ↺ Turn left — spin 90° in place (now you face a new way)
• The robot starts at S, facing up (↑)

Card 1 — Make a Square

Goal: Drive a square loop and come back to S, facing up — just like you started.

The robot’s program: ↑ Forward 3 → ↻ Turn right → Forward 3 → ↻ Turn right → Forward 3 → ↺ Turn LEFT → Forward 3

Trace it:

.  .  .  .  .  .
.  .  .  .  .  .
.  .  .  .  .  .
.  .  .  .  .  .
S  .  .  .  .  .

• The wrong step is:
• It should say:
• So the robot really ends up:

Card 2 — Reach the Flag

Goal: Stop on the flag (F).

The robot’s program: ↑ Forward 3 → ↻ Turn right → Forward 3

Trace it:

.  .  .  F  .  .
.  .  .  .  .  .
.  .  .  .  .  .
.  .  .  .  .  .
.  .  .  .  .  .
S  .  .  .  .  .

• The wrong step is:
• It should say:
• So the robot really ends up:

Card 3 — Turn the Corner

Goal: Drive up, make a clean square corner, then drive straight to the parking spot P (an “L” shape). P is straight to the right of the corner.

The robot’s program: ↑ Forward 3 → ↻ Turn right 45° → Forward 3

Trace it:

.  .  .  .  .  .
.  .  .  .  .  .
.  .  .  .  .  .
.  .  .  P  .  .
.  .  .  .  .  .
S  .  .  .  .  .

• The wrong step is:
• It should say:
• So the robot really ends up:

Card 4 — Around the Block

Goal: Weave around the wall (▒) and stop on P.

The robot’s program: ↑ Forward 2 → ↻ Turn right → Forward 2 → ↺ Turn left → Forward 2 → ↺ Turn LEFT → Forward 2

Trace it:

.  .  .  .  P  .
.  .  ▒  .  .  .
.  .  ▒  .  .  .
.  .  .  .  .  .
S  .  .  .  .  .

• The wrong step is:
• It should say:
• So the robot really ends up:

The Big Idea

One small wrong step throws off everything after it. That’s why today’s robot gets a gyro — to make its turns exact.