Grid Coding Adventure

Overview

This is lesson 3 of 8 in Bee-Bot Adventures Unplugged. Students build on earlier learning about algorithms by creating a themed floor grid and using arrow cards to describe a step-by-step route from a starting point to a destination. They practise sequence, decisions and checking an algorithm without using a physical Bee-Bot.

Learning intentions

Students will:

• identify a starting point, destination and obstacles on a floor grid
• sequence arrow commands to create an algorithm
• follow and describe a route accurately
• check and improve an algorithm when the route does not work

Success criteria

• I can draw a correct path from the start to the destination.
• I can place arrow cards in the correct order.
• I can explain my algorithm using words such as forwards, backwards, turn left and turn right.
• I can test my route and fix an error.

Curriculum links

• Digital Technologies — following and describing algorithms using sequence, decisions and repetition.
• Digital Technologies — investigating a familiar problem that can be solved using a digital system such as a robot.
• Digital Technologies — identifying and exploring components and commands used for a purpose.
• Design and Technologies — sequencing steps cooperatively when creating a designed solution.

Lesson structure (45 minutes)

1. 0–5 min · Hook and retrieve. Open with the hook and retrieval slides showing a zoo grid with a robot at the entrance and asking, “How could we help the robot reach the lion without getting stuck?” Students turn to a partner and recall what an algorithm is, naming one command they used in the previous lesson.

2. 5–12 min · Model an algorithm. Use the algorithm modelling slides to display a simple 4-by-4 grid, a start square, a destination and one obstacle; model placing arrow cards in order, thinking aloud about direction and demonstrating that one incorrect command changes the route. Students use finger movements to follow the route and identify where the robot would finish.

3. 12–17 min · Explain the challenge and roles. Show the instructions and teamwork slides and introduce groups of five: grid builder, destination manager, coder, robot and checker; rotate roles during the activity. Teacher explains that each group must create either a zoo or farm route, use at least four commands, keep the route within the grid and test it before recording it. Students repeat the task steps to a partner: build, plan, test, check and record.

4. 17–32 min · Build, code and test. Give each group floor-grid squares or masking-tape grid materials, themed picture cards, arrow cards and one obstacle card. Students create a 4-by-4 grid, place a start and destination, then arrange arrow cards to plan a route; the “robot” follows the commands while the checker points to each square. Groups adjust any incorrect algorithm and then record the final path on the grid coding worksheet. Teacher circulates, asks “What happens first?”, “How do you know which way is left?” and “What could you change?”, and checks that students describe commands in order.

5. 32–39 min · Partner route challenge. Return to the route-sharing slides and invite groups to swap their recorded route with a nearby group. The receiving group follows the diagram and arrow sequence, without being told the destination first, then reports whether the algorithm worked and identifies any unclear instruction. Students make one improvement if their partner finds an error.

6. 39–45 min · Plenary and assessment. Display the plenary slides with the prompts “What makes an algorithm clear?” and “Why is testing important?” Students share one successful command sequence and one correction they made. They complete the final reflection box on the grid coding worksheet, drawing an arrow to show the first move and explaining how they checked their route before handing it in.

Resources

• the Grid Coding Adventure slide deck
• the grid coding worksheet
• Floor-grid squares or masking tape
• Zoo and farm picture cards
• Arrow command cards with icons
• Start, destination and obstacle cards
• Open floor space
• Pencils, thick felt-tip pens and clipboards
• Optional counters or classroom objects as robots

Assessment

• During modelling, ask students to predict the result of a command sequence and explain why order matters.
• During group work, observe whether students identify a start and destination, sequence commands, follow directions and debug an error.
• Use the worksheet to assess whether the path reaches the destination and whether the student can represent or describe the first move and checking process.

Differentiation

• Support students with pre-drawn grid templates on the worksheet, fewer obstacles, a shorter route and arrow cards that include large, clear images and directional words. Read instructions aloud and provide one command at a time for students who need reduced cognitive load.
• Use high-contrast colours, uncluttered layouts, large sans-serif text and symbol-supported command cards for dyslexic learners. Avoid requiring students to read long instructions; pair spoken directions with demonstrations and allow oral explanations or drawing.
• Support EAL learners with gestures, repeated modelling and sentence starters such as “First, the robot…”, “Next, it…”, and “The route worked because…”.
• Assign purposeful group roles and allow students to work with a supportive partner. Provide a taped grid or ready-made template where motor planning, attention or fine-motor difficulties make construction challenging.

Extension

• Challenge advanced learners to create two different routes to the same destination and explain which is more efficient.
• Ask learners to include a decision point, such as “If the square is blocked, turn right; otherwise move forwards”, or a repeated pattern such as “move forwards twice”.
• Invite students to design a route that another group must decode using only the diagram and arrow sequence.