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Fewer Steps to the Goal

Many paths can reach the same treasure. A better route uses fewer moves. Compare plans and pick the shorter one.

Class 3 to 5beginner15 min3 lessons1 interactive lab
By the end you will be able to
  • Count steps in two different plans to the same goal
  • Choose the plan with fewer moves when both work
  • Explain why a shorter plan is easier to fix and remember

Finish first

Lesson 1 of 3

Two paths, one prize

On a grid you might reach the flag by going around the top or along the bottom. Both can work if there are no walls. The question is which uses fewer forwards and turns.

Count every forward and every turn as one step unless your teacher says otherwise. A plan with eight steps is longer than a plan with five, even if it looks prettier on paper.

In the robot lab, try two saved plans to the same flag. Run both and watch the step counter. The shorter successful plan wins.

Interactive lab

Robot planner

Run two plans to the same flag and compare how many steps each one takes.

Robot planner

Sequences, turns, repeats and choices
The plan
  1. Forward
  2. Forward
  3. Forward
1 / 4

Start

The robot starts here, facing right. The plan has 3 steps. It will follow them exactly, even when that is wrong.

Continue

Lesson 2 of 3

Shortcuts that are real

A shortcut is not a diagonal cheat through a wall. It is a different open path that skips unnecessary detours. If the map shows a straight corridor, use it.

Sometimes a path looks shorter but needs extra turns. Three forwards in a row beats forward, turn, forward, turn, forward if both are safe.

Ask: did I walk past the goal and come back? That U-shape often means you can trim steps.

Continue

Lesson 3 of 3

Better plans in life

Choosing a shorter safe path is like picking the quickest walk between two classrooms without running through the flower bed.

Computers care about efficiency too. Delivery apps compare routes so drivers do not waste fuel. You are practising the same comparison on a tiny grid.

Next you will meet walls that force you to take a longer path on purpose. Shortest and safest both matter.

Continue

Practice

Work these out yourself

No answer key here on purpose: these are the questions worth thinking through before you move on. Open one and work it out.

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Assessment

Check your understanding

Answer each question, then read the explanation. That is where the learning is.

0/4
  1. Question 1: Two plans reach the treasure. Plan A uses six steps and Plan B uses nine. Which is better if both are safe?
    Question 1 / 4

    Two plans reach the treasure. Plan A uses six steps and Plan B uses nine. Which is better if both are safe?

    Select an option first
  2. Question 2: What is a real shortcut on a grid?
    Question 2 / 4

    What is a real shortcut on a grid?

    Select an option first
  3. Question 3: Why count turns as well as forwards?
    Question 3 / 4

    Why count turns as well as forwards?

    Select an option first
  4. Question 4: A U-shaped path passes the goal and returns. What might you do?
    Question 4 / 4

    A U-shaped path passes the goal and returns. What might you do?

    Select an option first
4 of 4 questions left.

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