Lesson Plan

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Lesson Plan
Grade: Date: 25/02/2026
Subject: Physics
Lesson Topic: Explain that the sum of the currents into a junction is the same as the sum of the currents out of the junction
Learning Objective/s:
  • Describe Kirchhoff’s Current Law and its significance for charge conservation.
  • Apply KCL to determine unknown currents in series and parallel circuits.
  • Analyse circuit diagrams by identifying junctions and writing KCL equations.
  • Solve numerical problems using KCL combined with Ohm’s law.
Materials Needed:
  • Projector or interactive whiteboard
  • Circuit simulation software (e.g., PhET)
  • Worksheets with circuit diagrams and practice problems
  • Multimeter for demonstration
  • Whiteboard and markers
  • Rulers and pencils
 Introduction:
Begin with a quick demonstration of water flowing through pipes that split and rejoin, linking the idea to electric current. Recall the students’ prior learning of series and parallel circuits and the concept of current direction. Explain that by the end of the lesson they will be able to use Kirchhoff’s Current Law to predict how current divides at any junction.
Lesson Structure:
  1. Do‑now (5'): Students complete a short exit ticket from the previous lesson on series circuits.
  2. Mini‑lecture (10'): Introduce KCL with the water‑pipe analogy and present the algebraic form ∑Iin=∑Iout.
  3. Guided practice (15'): Work through the illustrative parallel‑circuit example on the board; students fill in the missing currents.
  4. Collaborative activity (15'): In pairs, use circuit simulation to build a three‑branch circuit, identify junctions, write KCL equations, and solve for unknown currents.
  5. Check for understanding (5'): Quick quiz using clickers or a show‑of‑hands on common mistakes.
Conclusion:
Summarise that the total current entering a node equals the total current leaving, reinforcing charge conservation. Ask each pair to share one solution they found challenging as an exit ticket. Assign homework: a worksheet with three new junction problems to be completed for the next class.