Lesson Plan

• Describe the core services an operating system provides (resource management, hardware abstraction, security, etc.).
• Explain how an OS enables multitasking and protects applications from one another.
• Compare system behavior with and without an OS using concrete examples.
• Interpret a basic CPU‑utilisation formula and relate it to scheduling decisions.
• Evaluate the importance of the OS for user interaction and system reliability.

• Projector and screen
• Slide deck summarising OS services
• Printed comparison table (with vs. without OS)
• Handout with a simple file‑locking scenario
• Computers (or laptops) with a basic OS for demo
• Sticky notes or cards for the resource‑allocation activity
• Exit‑ticket slips

Begin by asking students to name everyday devices they use (smartphone, game console, ATM) and what they think makes these devices usable. Briefly recall prior learning about hardware components. State that by the end of the lesson they will be able to articulate why a dedicated operating system is essential for such devices.

1. Do‑Now (5') – Quick think‑pair‑share: List three functions a computer must perform before any program runs.
2. Mini‑lecture (10') – Present slide deck covering OS services (resource management, abstraction, UI, security, multitasking, file & device management).
3. Interactive comparison (10') – Students examine the printed “With vs. Without OS” table, discuss differences in small groups, and report key contrasts.
4. Demonstration (10') – Live demo of file locking on a computer: show how two processes safely write to the same file using OS system calls.
5. Group activity (15') – Resource‑allocation simulation using sticky‑note cards to represent CPU time, memory, and I/O; students act as the OS scheduler.
6. Formative check (5') – Exit ticket: Write one reason an OS is indispensable and one real‑world example.

Summarise how the OS abstracts hardware, manages resources, and safeguards system stability. Collect exit tickets to gauge understanding and assign a brief homework: research a specific OS (e.g., Linux, Android) and identify one unique service it provides.