Introduction to Forces: Pushes and Pulls

Active learning works for forces because students need to feel the difference between pushes and pulls to build lasting mental models. When Year 7 students tug ropes, slide objects, and drop magnets, they connect abstract ideas to their own physical experiences, making concepts like friction and gravity memorable and meaningful.

• Year 7
• Science
• 4 activities
• 20 min–45 min

Learning Objectives

1. Identify and classify examples of contact and non-contact forces.
2. Explain how balanced and unbalanced forces affect an object's motion.
3. Measure the magnitude of forces in Newtons using a spring balance.
4. Analyze scenarios to determine the net effect of multiple forces acting on an object.

Inquiry Circle

⏱ 30 min·Whole Class

Whole Class Demo: Tug-of-War Balances

Split class into two teams holding a rope attached to newtonmeters. Pull gently until forces balance (rope still), then unbalance to observe motion. Record readings on shared chart. Follow with class vote on predictions for next pulls.

Prepare & details

Explain what causes an object to start or stop moving.

Facilitation Tip: During Tug-of-War Balances, have students stand on marked spots to emphasize that equal and opposite pulls create balance, visible in the stillness of the rope.

Setup: Groups at tables with access to source materials

Materials: Source material collection, Inquiry cycle worksheet, Question generation protocol, Findings presentation template

• Analyze
• Evaluate
• Create
• Self-Management
• Self-Awareness

Inquiry Circle

⏱ 45 min·Small Groups

Small Groups: Contact Force Stations

Set up stations with sandpaper ramps for friction pushes, rubber bands for tension pulls, and toy cars for applied force. Groups measure with newtonmeters, note effects on motion, and rotate stations. Share one key observation per group.

Prepare & details

Differentiate between contact and non-contact forces.

Facilitation Tip: At Contact Force Stations, circulate with a timer to keep groups rotating every 6 minutes, ensuring all students interact with friction, tension, and normal forces.

Setup: Groups at tables with access to source materials

Materials: Source material collection, Inquiry cycle worksheet, Question generation protocol, Findings presentation template

• Analyze
• Evaluate
• Create
• Self-Management
• Self-Awareness

Inquiry Circle

⏱ 35 min·Pairs

Pairs: Non-Contact Force Drops

Partners drop objects like feathers and balls from heights to feel gravity's pull, then use magnets to attract paperclips across tables. Measure pull strength at distances with balances. Compare data in pair discussions.

Prepare & details

Analyze how balanced and unbalanced forces differ in their effects.

Facilitation Tip: For Non-Contact Force Drops, assign roles so one student drops the magnet while another times the fall, making the invisible force of magnetism concrete through shared observation.

Setup: Groups at tables with access to source materials

Materials: Source material collection, Inquiry cycle worksheet, Question generation protocol, Findings presentation template

• Analyze
• Evaluate
• Create
• Self-Management
• Self-Awareness

Inquiry Circle

⏱ 20 min·Individual

Individual: Force Diary Challenge

Students list five daily pushes or pulls, estimate force in newtons, then test one with a spring balance like opening a door. Sketch before-and-after motion. Share top example in plenary.

Prepare & details

Explain what causes an object to start or stop moving.

Facilitation Tip: In the Force Diary Challenge, provide sentence starters like 'Today I pushed the trolley with a force of...' to guide students in accurately recording forces and outcomes.

Setup: Groups at tables with access to source materials

Materials: Source material collection, Inquiry cycle worksheet, Question generation protocol, Findings presentation template

• Analyze
• Evaluate
• Create
• Self-Management
• Self-Awareness

Teaching This Topic

Teach forces by starting with what students already do—push, pull, throw, and drop—then layer scientific language and measurement. Avoid abstract explanations alone; instead, let students test predictions with hands-on tools. Research shows that combining visual demonstrations with collaborative data collection helps students grasp the invisible nature of forces and reduces misconceptions about balanced forces and net effects.

What to Expect

Successful learning shows when students can identify pushes and pulls in everyday actions, measure forces in newtons, and explain how balanced and unbalanced forces affect motion. By the end of the lessons, they should confidently use tools like spring balances and describe forces with precise vocabulary.

Watch Out for These Misconceptions

Common Misconception

During Small Groups: Contact Force Stations, watch for students who assume all pushes are stronger than pulls.

What to Teach Instead

Have students compare the sensation of pushing a heavy box across the floor with pulling a backpack on a smooth surface. Ask them to describe the effort in each action and record which felt stronger, then discuss why direction matters in force interactions.

Common Misconception

During Whole Class Demo: Tug-of-War Balances, watch for students who think balanced forces mean no forces are acting.

What to Teach Instead

After the tug-of-war, have students hold the rope still in the middle while you ask: 'Is the rope moving? What does that tell us about the forces?' Then, have them place a book on a spring balance to see opposing forces in action.

Common Misconception

During Small Groups: Contact Force Stations, watch for students who believe a stronger push always causes faster motion.

What to Teach Instead

Provide identical trolleys and ask groups to push with varying forces while measuring acceleration with a stopwatch. Have students plot force vs. speed on graph paper and discuss why mass also matters in the relationship.

Assessment Ideas

Exit Ticket

After Whole Class Demo: Tug-of-War Balances, provide a diagram of a stationary book on a table. Ask students to list all forces, label each as contact or non-contact, and state whether the forces are balanced or unbalanced. Collect responses to identify misconceptions before the next lesson.

Quick Check

During Small Groups: Contact Force Stations, ask students to hold a spring balance with a 100g mass attached. Have them read the force in newtons, then gently pull upward and observe the change in the reading. Ask: 'Why did the number increase when you pulled upward?' to assess understanding of net force.

Discussion Prompt

After Whole Class Demo: Tug-of-War Balances, present the scenario: 'A tug-of-war team pulls with 500N, and the opposing team pulls with 450N. Describe what happens to the rope and explain why, referencing balanced and unbalanced forces.' Use student responses to gauge comprehension of net force and motion.

Extensions & Scaffolding

• Challenge: Ask students to design a simple game using pushes and pulls that demonstrates balanced forces, like a seesaw with equal weights.
• Scaffolding: Provide a word bank and force diagram templates for the Force Diary Challenge for students who need structure.
• Deeper exploration: Let students research how engineers use force calculations to design seatbelts or playground equipment, then present findings to the class.

Key Vocabulary

Force	A push or a pull on an object that can cause it to change its state of motion.
Newton (N)	The standard unit of force, named after Sir Isaac Newton. One Newton is the force needed to accelerate a 1kg mass at 1m/s².
Contact Force	A force that requires direct physical contact between two objects, such as friction or a push.
Non-Contact Force	A force that can act on an object without physical contact, such as gravity or magnetism.
Balanced Forces	When two or more forces acting on an object are equal in magnitude and opposite in direction, resulting in no change in motion.
Unbalanced Forces	When forces acting on an object are not equal and opposite, causing a change in the object's motion (acceleration).