Engaging KS3 Science lesson on diffusion with visual tasks, questions & AfL. Explores particle movement in gases and liquids using real-life examples. This fully resourced PowerPoint (.pptx) lesson introduces KS3 students to the concept of diffusion, including definitions, particle behaviour, and factors that influence the rate of diffusion such as temperature, particle size, and state of matter. The lesson includes: Clear learning objectives and success criteria Real-world examples (e.g. perfume, food colouring) Visuals and diagrams of particle movement Structured tasks with scaffolded sentence starters and fill-in-the-blank activities Video-based observation and summary tasks Opportunities for self-assessment and peer explanation Exit card plenary and stretch questions for differentiation Ideal for KS3 Science (Year 7–9) and mapped to the national curriculum and particle model topic. Suitable for both specialist and non-specialist teachers. File type: .pptx (PowerPoint, editable and compatible with Microsoft Office or Google Slides). Keywords: diffusion, KS3 science, particle model, concentration gradient, temperature, Brownian motion, states of matter, gases, liquids, science PowerPoint, AfL, plenary, worksheet.