Lesson Plan

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Lesson Plan
Grade: Date: 17/01/2026
Subject: Physics
Lesson Topic: Determine whether an object floats based on density data
Learning Objective/s:
  • Describe the concept of density and its units.
  • Explain how density determines whether an object floats, sinks, or remains suspended.
  • Apply the density comparison method to predict flotation of various materials in water or other fluids.
  • Calculate density from mass and volume and use it in buoyancy decisions.
Materials Needed:
  • Projector or interactive whiteboard
  • Worksheets with density tables and practice problems
  • Sample objects (wood block, metal block, cork, etc.) and a water tank
  • Balance scales and measuring cylinders
  • Calculator or spreadsheet software
 Introduction:
Begin with a quick demonstration: drop a piece of wood and a metal nail into a water tank to spark curiosity about why they behave differently. Review students’ prior knowledge of mass, volume, and the formula for density. Explain that today they will learn to use density data to predict whether objects will float, sink, or stay suspended, and that success will be measured by correctly completing the worksheet and explaining their reasoning.
Lesson Structure:
  1. Do‑now (5'): Students calculate density of a given object from provided mass and volume on a mini‑quiz sheet.
  2. Mini‑lecture (10'): Review density formula, units, and the buoyancy condition using projector slides and a diagram.
  3. Guided practice (12'): Work through the worked example together, prompting students to compare densities and state the conclusion.
  4. Hands‑on investigation (15'): In small groups, students measure mass and volume of provided objects, determine their densities, predict flotation in water, then test predictions in the water tank.
  5. Class discussion & check for understanding (8'): Groups share results; teacher clarifies misconceptions and uses clicker questions to confirm understanding.
  6. Independent practice (10'): Students complete the worksheet’s practice questions, applying the step‑by‑step method.
Conclusion:
Summarise that flotation depends on the relative densities of the object and the surrounding fluid, reinforcing the comparison rule. Ask students to write a one‑sentence exit ticket stating the key criterion for an object to float. Assign homework to research the density of a household item and predict its behaviour in water.