Lesson Plan

• Recall that protons and neutrons are composite (baryon) particles, not fundamental.
• Describe the quark composition of a proton (uud) and a neutron (udd).
• Explain how the fractional charges of up and down quarks combine to give the integer charges of nucleons.
• Interpret a schematic diagram of nucleon quark structure, including spin direction.

• Projector and screen
• Whiteboard and coloured markers
• Printed handout with quark‑content table
• Interactive deep‑inelastic scattering simulation (online)
• Worksheet for charge calculations
• Diagram cards of proton and neutron for labeling

Begin with a striking image of particle collisions to spark curiosity about what lies inside atoms. Ask students what they already know about protons, neutrons, and the idea of “fundamental” particles. Explain that today’s success criteria are to identify nucleons as composite and to articulate their quark make‑up.

1. Do‑now (5'): Quick quiz on atomic structure and previous definitions of fundamental particles.
2. Mini‑lecture (10'): Explain why protons and neutrons are not fundamental, using deep‑inelastic scattering images.
3. Guided exploration (12'): Present the quark‑content table; students work in pairs to calculate the total charge of each nucleon.
4. Interactive simulation (8'): Students manipulate an online scattering demo to visualise internal quark structure.
5. Diagram labeling activity (10'): Using diagram cards, groups label up/down quarks and indicate spin arrows for both proton and neutron.
6. Check for understanding (5'): Exit ticket – one sentence describing why nucleons are composite.

Summarise that protons and neutrons consist of three quarks whose fractional charges add to the observed integer charges, reinforcing their status as composite particles. Collect exit tickets and remind students to complete the worksheet on other baryons for homework.