Networks and Communication — Year 4 Lesson Plan
National Curriculum: Computing KS2 — understand computer networks including the internet; how they can provide multiple services; the opportunities they offer for communication
Overview
Pupils develop their understanding of how computers communicate within networks. They learn the difference between a LAN and a WAN, understand the roles of key hardware (routers, switches, servers), explore how email and the web function as services on the internet, and consider both the benefits and risks of online communication.
Learning Objectives
- Explain the difference between a LAN and a WAN.
- Describe the roles of routers, switches, and servers in a network.
- Explain how email travels from sender to recipient.
- Identify the benefits and risks of communicating online.
Key Vocabulary
Suggested Lesson Structure
Ask: how does a message get from your computer to a friend's device on the other side of the world? Collect ideas. Establish: there is a lot of infrastructure involved that we never see when we click 'send'.
Introduce network types: LAN (our school network — computers, printers, and a server connected within the building); WAN (the internet — millions of connected LANs and individual devices across the world). Key hardware: switch (connects devices within a LAN), router (connects networks together and directs traffic), server (stores files or provides services — web servers store websites; email servers handle messages). How email works: sender → email client → outgoing mail server (SMTP) → internet → recipient's incoming mail server (IMAP/POP3) → recipient's email client. Compare with post: the mail server is like a sorting office. Communication risks: phishing, spam, impersonation — why we should never click unknown links or share passwords via email.
Network diagram activity: pupils label a diagram of a school network (computers, switch, router, server, internet connection) and annotate each component with its role. Then trace the path of an email from one school computer to a home device, labelling each step.
Pupils investigate a network-related scenario: a school's internet is slow. They are given three possible causes (faulty router, overloaded server, too many devices on the Wi-Fi) and must: explain what each would mean, suggest how to test each cause, and recommend a fix. Builds logical diagnostic thinking.
Discuss: what would happen if the school's router failed? (No internet access.) What if the server failed? (No access to saved files.) Why do organisations have backup systems? Introduce resilience as a design principle — the internet was originally designed to route around damage. How does this connect to packet switching from Year 5?
Common Misconceptions
- The internet and Wi-Fi are the same thing — Wi-Fi is a wireless way of connecting to a local network; the internet is the global network of networks.
- Emails are sent directly from one person's device to another — emails travel through a series of servers before reaching the recipient.
Prior Knowledge
Pupils should already be able to:
- KS1 online safety: basic understanding of the internet as a connected space.
- Year 3 Computing: experience using digital tools and saving files to a network.
- Understanding of input and output in computing systems.
Want a personalised version of this lesson?
Use Staffroom to generate a complete lesson plan tailored to your class — add context about ability, recent learning, or specific pupils and get a plan ready to teach. Free trial, no card required.