Science · Grade 1

Active learning ideas

Building Strong Foundations

Active learning works well for this topic because students need to feel how stability changes with different bases. When they build and test their own designs, they connect physical evidence to abstract concepts like weight distribution and center of gravity. This hands-on process builds lasting understanding better than abstract explanations alone.

• Ontario Curriculum Expectations
• K-2-ETS1-2

• 20–45 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Mystery Object
• 30 min · Pairs

Pairs Challenge: Narrow vs Wide Bases

Pairs construct two towers of equal height using blocks or straws: one with a narrow base, one with a wide base. They gently shake the table or add small weights to test stability, then record which tower stands longer. Pairs share findings with the class.

Explain how a wide base helps a tower stand tall.

Facilitation Tip

During the Pairs Challenge, remind students to keep tower height and materials identical except for the base shape so comparisons are fair.

What to look for

Present students with two pre-built towers, one with a narrow base and one with a wide base. Ask them to predict which tower will be more stable. Then, gently push each tower. Ask students to explain in one sentence why one tower was more stable than the other.

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

Activity 02

• Mystery Object
• 45 min · Small Groups

Small Groups: Heavy Load Foundation

Groups design and build a foundation using recyclables to support a heavy book or toy. They test by placing the load and shaking lightly, measure success by time standing, and redesign once if it fails. Discuss what made the best base.

Compare the stability of a structure with a narrow base to one with a wide base.

Facilitation Tip

In the Heavy Load Foundation activity, circulate with a set of test weights and ask each group to predict how many their base will hold before testing.

What to look for

Provide students with a drawing of a simple structure (e.g., a house outline). Ask them to draw a wider base for the structure and write one sentence explaining why their new base will make the structure more stable.

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

Activity 03

• Mystery Object
• 25 min · Whole Class

Whole Class: Shake Table Demo

As a class, build sample structures with varying bases on a shared shake table made from a tray on jelly. Shake together and vote on most stable. Chart results and predict improvements before a second round.

Design a foundation that can support a heavy object.

Facilitation Tip

For the Shake Table Demo, pause after each shake to ask students to point out where the tower’s base shifted and why.

What to look for

Ask students: 'Imagine you are building a tower to hold a heavy toy. What is the most important part of your tower to build first to make sure it doesn't fall over? Why is that part so important?' Listen for explanations related to the base and stability.

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

Activity 04

• Mystery Object
• 20 min · Individual

Individual: Base Sketch and Build

Each student sketches a stable base for a tower, then builds it individually with given materials. Test personally by stacking cups or blocks, note what works, and label sketch with changes for next try.

Explain how a wide base helps a tower stand tall.

Facilitation Tip

During the Base Sketch and Build, have students label their sketches with arrows showing how weight travels down the tower into the base.

What to look for

Present students with two pre-built towers, one with a narrow base and one with a wide base. Ask them to predict which tower will be more stable. Then, gently push each tower. Ask students to explain in one sentence why one tower was more stable than the other.

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

A few notes on teaching this unit

Teachers should emphasize that stability is a system of interacting factors, not a single rule. Avoid telling students the answers upfront; instead, guide them to notice patterns during testing. Research shows students grasp gravity and balance best when they manipulate objects themselves and explain their observations aloud to peers.

Successful learning looks like students using evidence from their tests to explain why wide bases support more weight and resist tipping. They should discuss how their tower’s base affects its stability and adjust designs based on observations. Peer conversations and shared data help solidify these ideas across the class.

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Watch Out for These Misconceptions

• During the Pairs Challenge, watch for students who assume taller towers are automatically more stable even after building a narrow tall tower that falls. Redirect by asking them to compare how weight spreads in their tall narrow tower versus their partner’s short wide tower.

  In the Heavy Load Foundation activity, have students add weights to both towers and point out how the narrow base’s center of gravity rises quickly, while the wide base stays low and spreads weight.

• During the Heavy Load Foundation activity, watch for students who believe glue alone can stabilize any base. Redirect by asking them to test their glued narrow base against an unglued wide base using the same weight.

  Pause during the Shake Table Demo and ask students to observe how glued seams crack on narrow bases first, while wide bases remain intact even without glue.

• During the Shake Table Demo, watch for students who think only side forces cause tipping. Redirect by asking them to add weight to the top of their tower and observe how it shifts the center of gravity outward.

  In the Base Sketch and Build, have students draw arrows showing weight pushing outward from the center when objects are placed high on their tower.

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Methods used in this brief

• Mystery Object