- Lenz law demonstrator: a simple, practical teaching and experimentation device designed for middle school physics. - How to use: operate in a windless environment and avoid external magnetic fields. Place the aluminium ring on the needle tip. The device runs quietly and is suitable as an electric power science project. - What it does: an experimental apparatus for explaining and demonstrating Lenz's law in a clear, observable way. - Benefits for learners: helps students grasp electromagnetic induction through hands-on observation, enhances engagement in physics lessons, and can support improvements in grades through practical experimentation. - Key attributes: - Function: demonstrates and explains Lenz's law. - Compatibility: appropriate for middle school physics curricula and lab activities. - Material: aluminium ring and needle-tip components used in the demonstration. - Performance: straightforward setup, quiet operation, reliable classroom use. - Use scenarios: 1) Classroom demonstration during magnetism and electricity units to visualize Lenz's law. 2) Student-led experiments in a controlled environment to explore the effects of surrounding conditions on the demonstration. 3) Physics project or science fair support as a practical learning aid in physics lessons.