Year 9

Science Support Materials

Science snapshot: Breathing rate/pulse rate and exercise

Science/Science Understanding/Biological sciences and Science Inquiry Skills/Planning and conducting; Processing and analysing data and information; Communicating

Content Description Relevant aspects of the Achievement Standards

Science Understanding

Multi-cellular organisms rely on coordinated and interdependent internal systems to respond to changes to their environment (ACSSU175)

Science Inquiry Skills

Planning and conducting

Plan, select and use appropriate investigation methods, including field work and laboratory experimentation, to collect reliable data; assess risk and address ethical issues associated with these methods (ACSIS165)

Select and use appropriate equipment, including digital technologies, to systematically and accurately collect and record data (ACSIS166)

Processing and analysing data and information

Analyse patterns and trends in data, including describing relationships between variables and identifying inconsistencies (ACSIS169)

Use knowledge of scientific concepts to draw conclusions that are consistent with evidence (ACSIS170)


Evaluate conclusions, including identifying sources of uncertainty and possible alternative explanations, and describe specific ways to improve the quality of the data (ACSIS171)

Critically analyse the validity of information in secondary sources and evaluate the approaches used to solve problems (ACSIS172)


Communicate scientific ideas and information for a particular purpose, including constructing evidence-based arguments and using appropriate scientific language, conventions and representations (ACSIS174)

They describe models of energy transfer and apply these to explain phenomena.

They design methods that include the control and accurate measurement of variables and systematic collection of data and describe how they considered ethics and safety.

They analyse trends in data, identify relationships between variables and reveal inconsistencies in results.

They analyse their methods and the quality of their data, and explain specific actions to improve the quality of their evidence.

They evaluate others’ methods and explanations from a scientific perspective and use appropriate language and representations when communicating their findings and ideas to specific audiences.

Nature of the assessment

Science investigation in which students plan and conduct an investigation to measure the effect of exercise on breathing rate and/or heart rate. They write a scientific report about their investigation.

Purposes of the assessment

To ascertain whether students understand the concept of a fair investigation (testing a hypothesis, controlling variables, appropriate measurement methods, appropriate presentation and analysis of data).

To ascertain whether students can evaluate their results and suggest modifications of their investigation.

To ascertain students’ understanding of the functioning of the respiratory and/or circulatory systems through the conclusions they draw after processing the results.

Stage in the teaching sequence

Early in a teaching sequence about the respiratory and/or circulatory system.

Assessment task

The effect of exercise on breathing rate and heart rate

  1. Plan an investigation to measure the effect of exercise on breathing rate and heart rate. You must plan how many subjects are in your sample, how you will measure breathing rate and heart rate, and the form and amount of exercise your subjects will undertake.

You will have access to digital watches.

  1. In your group discuss your investigation plans and agree on the most appropriate plan.
  2. Conduct your investigation, write up your results and evaluate these results.

Investigation Plan





Name the variables which must be controlled for this to be a fair test.


Draw a table to enter your results in.

Processing results:

What conclusions can you draw from your results?


How could this experiment be improved to provide more reliable results?

Scientific report:

Work on your own to write a report of your investigation.

Assessment process

The teacher observed the groups’ planning discussions and asked clarifying questions at this initial stage. She viewed the plans and discussed improvements. For example, she suggested that the breathing rate and heart rate must be measured before any exercise, what were appropriate and safe forms of exercise, the need to measure pulse with finger not thumb and the time needed to measure the breathing and pulse. She made a note of those students who had struggled to plan a fair investigation and the type of errors they had made.

The teacher observed the conduct of the investigation to ensure safety and to assess whether appropriate procedures were being used. She noted where incorrect procedures were used so that she could discuss these in future lessons.

She used the students’ scientific reports to assess students’ data processing and interpretation skills and to evaluate the quality of their data and to suggest improvements to the investigation.

Using the information

The teacher observed that there was a need to discuss better ways of planning and conducting the investigation with the whole class.

She identified a small group of students who needed further teaching of fundamental concepts.

She identified a group of more able students who would benefit from extension work and, based on her observations, set a task that required these students to average the breathing rates for different subjects before and then after exercise, and compare these by graphing the individual results and comparing trends.

She used some students’ responses as exemplars to discuss different ways of presenting the data.

Although not the central focus of the assessment, the teacher used student responses to gauge their understanding of the respiratory and circulatory systems.