In this series of two lessons, primary students continue to investigate force (push and pull) and motion by learning about the force of gravity and how it affects balance. In the first lesson, students are introduced to the concept of gravity, play a game of Gravity Says to discover their own center of balance. Other balance activities are included to add to the exploration. In the second activity, students balance a buddy on a pencil to study a balancing system and then write about their learning.
Teacher instructions, background material, student recording sheets, rubrics for scoring, patterns for balancing buddies, science writing page, and extensions are included.
A slideshow of all pages of this lesson can be found under the Physical Science Tab: Gravity and Balance at http://scienceandkidsactivities.com.
A Framework for K-12 Science
Scientific and Engineering Practices
• Carrying Out Investigations
• Analyzing and Interpreting Data
Core Idea PS2: Motion and Stability: Forces and Interactions
PS2.A: Forces and Motion How can one predict an object’s continued motion, changes in motion, or stability? By the end of grade 2. Objects pull or push each other when they collide or are connected. Pushes and pulls can have different strengths and directions. Pushing or pulling on an object can change the speed or direction of its motion and can start or stop it. An object sliding on a surface or sitting on a slope experiences a pull due to friction between the object and the surface that opposes its motion.
PS2.B: Types of Interactions
What underlying forces explain the variety of interactions observed?
By the end of grade 2. When objects touch or collide, they push on one another and can change motion or shape.
PS2.C: Stability and Instability in Physical Systems
Why are some physical systems more stable than others?
By the end of grade 2. Whether an object stays still or moves often depends on the effects of multiple pushes and pulls on it (e.g., multiple players trying to pull an object in different directions). It is useful to investigate what pushes and pulls keep something in place (e.g., a ball on a slope, a ladder leaning on a wall) as well as what makes something change or move.
PS3.C Relationship Between Energy and Forces
How are forces related to energy?
By the end of grade 2. A bigger push or pull makes things go faster, and faster motion can cause a bigger change in shape when things collide.
• Cause and Effect: Mechanism and Explanation