Connecting Computers — Year 3 Lesson Plan
National Curriculum: Computing KS2 — understand computer networks including the internet; how they can provide multiple services, such as the World Wide Web; and the opportunities they offer for communication and collaboration
Overview
Pupils learn how computers are connected to form networks and explore the role of key devices such as routers, switches, and servers. They investigate how data travels across a network in packets and begin to understand the internet as a global network of networks. The lesson uses diagrams, physical role-play, and discussion to make abstract concepts tangible.
Learning Objectives
- Explain what a computer network is and why networks are useful.
- Identify the key devices in a network and describe their roles.
- Describe how data travels across a network as packets.
- Understand that the internet is a worldwide network of networks.
Key Vocabulary
Suggested Lesson Structure
Human network role-play: give each pupil a card naming them as a computer, server, router, or switch. Use a ball of string to physically connect the devices as described. Ask: if the string is cut between two devices, what happens to data that needs to travel between them? Establish that there is often more than one path data can take.
Using a diagram, explain a Local Area Network (LAN): computers, a switch, and a router. The switch connects devices in the same network; the router connects the LAN to the wider internet. Introduce packets: large files do not travel whole — they are split into small packets, each labelled with a source and destination IP address. Different packets may take different routes. Show an animation or diagram of packets travelling from one computer to another. Introduce the internet: not a single thing, but millions of LANs connected by routers worldwide.
Pupils complete a labelled network diagram: given a set of devices (computers, printer, server, router), they draw connections and annotate each device's role. Then they trace a data journey: 'You want to load a webpage — what happens from your computer to the web server and back?' Pupils write the steps in order using the vocabulary correctly.
Pupils design their own school network on paper: how many computers? Where is the server? Where is the router? They write a sentence for each device explaining its role. Extension: what happens if the router fails? Can they redesign the network with redundancy — more than one route between points?
Quick-fire questions on mini whiteboards: What does a router do? What is a packet? What is an IP address? Close with a discussion: when you stream a video, what network infrastructure does it travel through between the studio and your screen?
Common Misconceptions
- Pupils often confuse the internet with the World Wide Web — the web is one service that runs on top of the internet; email, video calls, and gaming also use the internet.
- Data travels as a whole file — in reality, files are broken into packets that may take different routes and are reassembled at the destination.
Prior Knowledge
Pupils should already be able to:
- Basic understanding of what a computer is and what it does.
- Experience using the internet for research in KS1.
- Understanding that computers follow instructions (algorithms).
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