STEM Subject Choice: Factors that influence the decisions of Australian students entering Year 12

Author: David Jeffries

  • Thesis download: available for open access on 20 May 2021.

Jeffries, David, 2019 STEM Subject Choice: Factors that influence the decisions of Australian students entering Year 12, Flinders University, College of Education, Psychology and Social Work

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An advancing global economy and rapidly developing digital technologies signal the necessity to

develop citizens who are adequately equipped with science, technology, engineering and

mathematics (STEM) skills and the associated abilities to think critically and creatively for solving

problems effectively. Claims of STEM skills shortages in many Western countries (including

Australia) are coupled with a desire to enhance STEM capabilities of citizens to boost economic

productivity. Worryingly, there is a decline in STEM subject enrolment in senior secondary school

and university in recent decades.

This study builds on previous research that has identified individual characteristics such as gender,

SES, ethnicity, career aspirations, and the influences of peers and teachers on STEM educational

decisions. School level factors, such as average school SES and gender balance, have also been


Little research was found (in the researcher’s context of South Australia) that addressed STEM as a

whole subject choice in Year 12, where STEM as a whole refers to the collection of subjects from

curriculum areas of science, technology, engineering and mathematics. More specifically, the suite

of subjects categorised as STEM as a whole include high-level mathematics, science, engineering

and digital/information technology subjects. A detailed description is provided in Section

In order to address this gap, a mixed methods study investigating factors that influence students’

STEM subject enrolment choices was undertaken. This study used quantitative data from Australian

samples of students who participated in the Programme for International Student Assessment (PISA)

and the Longitudinal Surveys of Australian Youth (LSAY). These analyses were followed by a

qualitative study of the enrolment decisions of a different sample of senior secondary students in

South Australia.

The theory of planned behaviour (TPB) was the guiding conceptual framework for the collection,

analysis and interpretation of data. This research was approached with a pragmatist worldview,

highlighting the need to attend to the quantitative phase of the research with a post-positivist lens,

and the qualitative phase of the research with an interpretivist lens.

In the quantitative phase, a combination of single-level and multilevel multiple regression and

structural equation models identified factors that influence students’ decisions about enrolling in a

STEM subject in Year 12. Gender and immigrant status were shown to influence STEM enrolment

decisions, but they were mediated by variables including attitudes towards science and achievement

in science and mathematics. School level factors such as location, ratio of females, ratio of native

(at least one parent born in Australia) students and average school SES seemed to moderate the

student-level relationships. The qualitative phase used interview data from 20 participants. Factors

such as attitudes towards STEM, perceived norms, perceived behavioural control, and other

background factors influenced STEM enrolment decisions.

The majority of findings from both phases of the study are consistent with prior research findings.

However, some add to the literature e.g. the differences in STEM enrolment patterns between native

students and those from migrant backgrounds, while others suggest the need for further research.

A synthesis of the findings provides a more nuanced account of the complex phenomena

investigated in this research and helps to explain how students might navigate the STEM subject

decision-making process entering Year 12. It is suggested that the TPB be expanded to

accommodate multilevel or nested data. Research findings presented in this thesis have implications

for students and their families along with teachers and leaders within schools. A greater

understanding of how decisions are made to enrol in STEM subjects in Year 12 will enable all

stakeholders to have more effective discussions, resulting in students following more considered

and appropriate pathways into post school education and careers in STEM and in turn meeting the

economic and social needs of our rapidly changing society.

Keywords: STEM; subject choice; SEM; mixed methods; PISA; LSAY; multilevel modelling; structural equation modelling;

Subject: Education thesis

Thesis type: Doctor of Philosophy
Completed: 2019
School: College of Education, Psychology and Social Work
Supervisor: Lindsey Conner