Students see for themselves how gravity acts to pull objects.
Activity A2: Marvellous marbles and reliable ramps [PDF, 191 KB]
How to use this activity
This is a hands-on exploratory activity which involves the students rolling a marble down a ramp.
Repeat 3 times from one starting point and average the results, then change the angle of the ramp.
Discussion about keeping the launch point of the marble the same each time will assist students to understand the need for a consistent method if their results are to have meaning or be compared to another group's results.
At some stage, introducing the terms “variables” (in this case the angle of the ramp) and “constants” (in this case the launch position) may be appropriate. Aim to encourage student talk in order to find a relationship between gravity, angle and speed.
This activity is adapted from Building Science Concepts Book 42: Marbles. Additional content support for teachers can be found in this book.
Book 42: Marbles: Exploring Motion and Forces (TKI - Science online)(external link)
Where it fits in the NZ Curriculum
Nature of Science strand
Investigating in Science – ask questions, find evidence, explore simple models and carry out appropriate investigations to develop simple explanations (Level 3-4).
- Science activities can be used to develop any of the Nature of Science sub strands.
- Identify aspects of Investigating in Science that your students need to get better at or understand more fully.
- Then frame your unit to be very clear about these things when you do them.
NZ Curriculum | Science achievement objectives(external link)
Gather and interpret data, use evidence.
The five science capabilities (TKI - Science online)(external link)
Physical World. Explore, describe and represent patterns and trends for everyday examples of physical phenomena, such as movement, forces (Level 3-4).
Big science idea
Gravity is a force which acts to pull objects.
Friction is a force between objects when they move over one another. It can be both useful and a problem.
- Gravity is a force pulling objects toward the Earth.
- Changing a ramp's angle changes the total pull on an object.
- It is important to keep some things the same (constants) so that we can reliably test what we are measuring (variables).
For example, in this experiment, if the release point of the marble is not consistent it will not be possible to be sure of your results.
- Measurements are needed to describe our observations accurately.
- There are similarities and differences in what we observe.
Possible learning objectives
The students can...
- identify the things which need to be kept the same in their experimental trials (constants) and what they are going to change (variables)
- use accurate measurements to make detailed observations
- identify and describe patterns involving similarities and differences
- compare trial results with other groups of students. Where there are differences, students can make statements/inferences about the reason for any differences
- describe the relationship between gravity and angle
- link gravity and angle in this investigation to another experience they have had in their lives.