Science Extension 2025 HSC exam pack

Students should:

• read the question carefully to ensure that they do not miss important components of the question
• have a clear understanding of key words in the question and recognise the intent of the question and its requirements
• use syllabus glossary definitions as a starting point to develop their responses
• plan the response to assist in the logical sequencing of information
• plan responses and monitor time, to allow for thorough critical analysis of each question
• communicate ideas and information using appropriate scientific terminology
• engage with the stimulus material provided
• present a logical and coherent response that addresses the question
• review their response to ensure that it addresses the question requirements
• review their response to ensure there are no contradictions.

Question 1

In better responses, students were able to:

• identify the purpose, audience and context
• describe implications associated with the suitability of publishing in a scientific journal, for example, publishing in a scientific journal may mean the article is peer-reviewed increasing the trustworthiness of the communication
• describe the strengths and/or limitations associated with presenting this image to communicate the findings
• provide reasons why the mode and media may or may not be suitable.

Areas for students to improve include:

• describing the suitability of the mode and media, rather than identifying features of the mode and media
• addressing how both the mode and media are used to communicate scientific findings.

Question 2 (a)

In better responses, students were able to:

• demonstrate a clear understanding of the use of a chi-squared test
• link the use of a chi-squared test to the stimulus material
• provide clear reasoning as part of the justification.

Areas for students to improve include:

• describing the unique features of a chi-squared test
• differentiating between the uses of different types of inferential statistics tests.

Question 2 (b)

In better responses, students were able to:

• clearly link the stimulus to the limitations of the study
• integrate statistical data into their response
• produce a clear judgement regarding the confidence of the conclusions drawn in the study.

Areas for students to improve include:

• interpreting inferential statistics
• exploring the impact of problems with the research, rather than just identifying issues.

Question 3

In better responses, students were able to:

• link the stimulus to their responses using specific data
• analyse a broad range of data from the stimulus.

Areas for students to improve include:

• addressing economic, political and global impacts
• linking interpretation of data to their response to directly address the question
• ensuring there is a focus on the stimulus, rather than drawing only on examples from prior knowledge.

Question 4 (a)

In better responses, students were able to:

• describe the benefits and limitations of collecting and processing a large dataset
• support arguments with the use of specific details from the source
• make an informed and clear judgement on the accuracy of the conclusions drawn from the dataset provided.

Areas for students to improve include:

• developing an evaluation that incorporates benefits and limitations of the data collection process
• ensuring a clear connection between the arguments provided and the final judgement.

Question 4 (b)

In better responses, students were able to:

• integrate specific details from the spreadsheet to support their explanation, such as the features of the frog calls
• identify features of spreadsheets that allow for data manipulation.

Areas for students to improve include:

• using examples from the source to support their response, for example, describing how the spreadsheet can be cleansed and analysed for a project.

Question 4 (c)

In better responses, students were able to:

• address the conclusion provided in the question
• provide examples that describe how data is processed and analysed to draw a conclusion
• demonstrate a complete process that would allow for a conclusion to be drawn from the source specified.

Areas for students to improve include:

• describing methods that can be used to analyse qualitative data, for example, content or thematic analysis.

Question 5

In better responses, students were able to:

• identify how each of the named methods of scientific inquiry were present in the stimulus, for example, linking qualitative research to the identification of a precipitate
• evaluate the appropriateness of each of the named methods of inquiry to the study, that is, primary and secondary research, induction and deduction, qualitative and quantitative research
• provide a logical and coherent flow to their response, with clear links to the concepts and ideas presented.

Areas for students to improve include:

• differentiating between the methods of scientific inquiry and the steps taken in the study
• ensuring that the stimulus material is integrated throughout the response
• evaluating the method of inquiry, rather than the abstract or the study.