Why can we feel gravity pull us down towards the Earth, but not sideways towards other big objects like buildings? Why do the planets in our solar system orbit the sun instead of flying off into space? In this lesson plan your students will develop a model for gravity and use it to explore answers to these questions.
This lesson helps students prepare for these Next Generation Science Standards
Construct and present arguments using evidence to support the claim that gravitational interactions are attractive and depend on the masses of interacting objects.
- MS-ESS1-2. Develop and use a model to describe the role of gravity in the motions within galaxies and the solar system.
This lesson focuses on these aspects of NGSS Three Dimensional Learning:
|Science & Engineering Practices
||Disciplinary Core Ideas
|Developing and Using Models.
Develop and use a model to describe phenomena.
Evaluate limitations of a model for a proposed object or tool.
||PS2.B: Types of Interactions. Gravitational forces are always attractive. There is a gravitational force between any two masses, but it is very small except when one or both of the objects have large mass—e.g., Earth and the sun.
ESS1.B: Earth and the Solar System. The solar system consists of the sun and a collection of objects, including planets, their moons, and asteroids that are held in orbit around the sun by its gravitational pull on them.
|Scale, Proportion and Quantity. Time, space, and energy phenomena can be observed at various scales using models to study systems that are too large or too small.
Systems and System Models. Models can be used to represent systems and their interactions.
Models are limited in that they only represent certain aspects of the system under study.
Ben Finio, PhD, Science Buddies
These materials will be enough to set up the activity for the entire class. For a large class, you may want to split into two groups, so you will need twice as many materials. The following supplies are available from
- Large sheet of stretchy fabric (polyester/spandex/lycra etc.), approximately 2 yards by 2 yards.
- Marble set that includes larger "shooter" marbles in addition to regular marbles.
- At least one pool ball, which you can purchase as a set or individually. Other heavy, round objects like oranges or grapefruit will also work.
- Lots of duct tape or masking tape, or spring clamps (at least twice as many as you have chairs). Make sure the jaws of the spring clamps open wide enough to clip onto the back of your chairs.
- 8–10 chairs (more if you have a bigger piece of fabric)
Be the first one to review
Entire class (two groups for large class)
Mass, gravity, orbit
- Explain why, on Earth, we can only feel gravity pulling us down, and not sideways towards other objects.
- Explain how gravity influences the motion of planets in our solar system.
- Understand the usefulness of models as well as their limitations.