Making bubbles II

Making bubbles II

Pencil and paperOnline interactive
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Working with Students
Further Resources
This task is about critiquing the variables in a fair test.

Question 1Change answer

Mereani planned an investigation to find out which was the best washing-up liquid for making bubbles. This was her plan:   
  • Add a few drops of washing-up liquid to 20 ml water, at room temperature.
  • Use a loop of wire, put it in the mixture, take it out, blow, and count the bubbles.
  • Add a few drops of a different washing-up liquid to another 20 ml container of water at room temperature.
  • Use another loop of wire, put it in the mixture, take the loop out, blow, and measure how long the bubbles last.
There are several problems with Mereani's plan. What are four things she should change in her plan so that the investigation will be a "fair test"?
Task administration: 
This task can be completed with pencil and paper or online.
Level:
5
Curriculum info: 
Science, Investigating in science, Material World
Key Competencies: 
Thinking
Keywords: 
properties, society, detergents, fair testing, variables, evaluation, investigation
Description of task: 
Students outline four ways of improving a given plan for an investigation to make it a fair test.
Curriculum Links: 
Science capabilities
The capabilities focus is brought about by the conversations you have and the questions you ask.
Capability: Gather and interpret data
This resource provides opportunities to discuss making decisions about the best way to collect data to answer a question.
Science capability: Gather and interpret data (TKI)
 
Science capabilities: 
Gather and interpret data
Answers/responses: 
   Y9 (05/1997) Y10 (05/1997)
Any 4 of:

•   Use only one measure: number of 
     bubbles or time bubbles last.
•   Use the same number of drops of
     washing-up-liquid.
•   Maintain constant strength of blow.
•   Repeat trialling.
•   Use the same loop of wire.

 4 correct – very difficult
3 correct – difficult
2 correct – moderate
1 correct – easy		 4 correct – very difficult
3 correct – difficult
2 correct – moderate
1 correct – easy
Diagnostic and formative information: 

Analysis of Correct Responses

Answer

Number of times given

Use same loop of wire

64

Use same number of drops of washing-up-liquid

61

Use only one measure

55

Maintain constant strength of blow

25

Repeat trialling

10