Principles of the Physical World: Senior Cycle Physics · 5th Year

Active learning ideas

Things That Stay Still or Keep Moving

Active learning works for this topic because students need to feel the difference between rest and motion directly. Handling objects that resist change builds intuition beyond abstract definitions. The activities let students test their own ideas, which is essential when misconceptions about forces and motion feel intuitive but are wrong.

• NCCA Curriculum Specifications
• NCCA: Primary Curriculum - Science - Energy and Forces

• 20–35 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Experiential Learning
• 25 min · Small Groups

Demonstration: Index Card Flick

Place a coin atop an index card stretched over a cup. Students flick the card sharply sideways; the coin drops into the cup due to inertia. Groups repeat with varying flick speeds and coin masses, recording outcomes and predicting results.

Why does a ball stop rolling if you don't keep pushing it?

Facilitation Tip

For the Index Card Flick, remind students to flick the card sharply and directly downward so the coin’s inertia keeps it in place while the card moves.

What to look for

Provide students with three scenarios: a book on a table, a rolling ball, and a person in a car. Ask them to write one sentence for each scenario explaining how inertia affects the object and what force is needed to change its motion.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Activity 02

• Experiential Learning
• 35 min · Pairs

Low-Friction Cart Push

Set up smooth tracks or rulers as low-friction surfaces. Students push toy cars or carts with equal force, measure travel distances, and compare to rough surfaces. Discuss net forces like air resistance and friction.

What makes a toy car stay in place until you push it?

Facilitation Tip

In the Low-Friction Cart Push, ask students to measure the distance traveled after each push and compare how a heavier load slows acceleration more than a lighter one.

What to look for

Pose the question: 'Imagine you are on a bus that suddenly brakes. Describe what happens to your body and explain why, using the term inertia. What force eventually stops you?' Facilitate a class discussion where students share their explanations.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Activity 03

• Experiential Learning
• 30 min · Pairs

Seatbelt Simulation

Hold a raw egg or small ball against a partner's chest with a string 'seatbelt.' Jerk forward suddenly to simulate braking; without restraint, the object continues forward. Pairs switch roles and vary speeds.

How does a seatbelt help you when a car stops suddenly?

Facilitation Tip

During the Seatbelt Simulation, have students time how long it takes for the dummy to come to rest with and without the ‘seatbelt’ (string) so they see the difference in stopping time.

What to look for

Show a short video clip of a common event like a skateboarder stopping abruptly. Ask students to identify the object exhibiting inertia, describe its initial state of motion, and explain what force is acting to change that motion.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Activity 04

• Experiential Learning
• 20 min · Whole Class

Class Line March

Whole class forms a line holding shoulders. Leader stops abruptly; observe chain reaction of bodies continuing forward. Debrief on inertia in crowds or buses.

Why does a ball stop rolling if you don't keep pushing it?

Facilitation Tip

For the Class Line March, use a stopwatch to record how long it takes each student to stop when you call ‘freeze,’ then discuss how their inertia affects the stopping distance.

What to look for

Provide students with three scenarios: a book on a table, a rolling ball, and a person in a car. Ask them to write one sentence for each scenario explaining how inertia affects the object and what force is needed to change its motion.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

A few notes on teaching this unit

Research shows that hands-on motion activities reduce the persistence of Aristotelian ideas about motion. Avoid over-explaining inertia before students experience it; let their observations drive the discussion. Use consistent language, such as ‘net force’ and ‘inertial mass,’ so students build accurate mental models from the start.

Students will confidently explain that objects stay still or move steadily unless a net force acts, and they will connect this to real-world examples like seatbelts. They should use correct language, such as inertia as a property, not a force. Observing peers’ trials will help them refine their models of motion.

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Watch Out for These Misconceptions

• During the Low-Friction Cart Push, watch for students attributing the cart’s slowing to ‘running out of push’ rather than friction or air resistance.

  Ask students to push the cart on different surfaces and compare distances: a smooth floor versus a carpet. This lets them see how friction changes motion, reinforcing that slowing requires a force.

• During the Index Card Flick, watch for students explaining the coin’s movement as the card ‘pushing’ it forward.

  Have students repeat the flick while gently blowing on the coin after the card moves to show that air does not cause the coin to move; inertia keeps it in place.

• During the Class Line March, watch for students describing stopping as a result of ‘the force running out.’

  Ask students to explain why they keep moving forward after ‘freeze’ is called. Have them model the motion with their hands to show their own inertia in action.

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Methods used in this brief

• Experiential Learning