CHAPTER 5 RESULTS SHOWING SCOPE AND QUALITY OF RESEARCH ON
5.3 THE SCOPE OF RESEARCH DONE
been publishing for their peers as Jenkins (2000) suggests. Instead, there has been some move towards making research outcomes available to practitioners as well.
In summary, in answer to research question 1a, extensive searches, using academic databases as well as non-electronic means, identified 101 reports which were subsequently obtained. After scrutiny, 41 reports (mostly published this century) were found to be suitable for critical analysis. They were published in journals with a target audience including both researchers and educational practitioners, with more than half of the reports appearing in internationally recognised peer reviewed journals. A secondary source, as cited by other authors, was also included.
From the table it can be seen that research on students in Europe predominates, with research on Asian students having also been reported frequently. Few reports arose from research in Africa and nothing suitable was reported from South America. From this it can be seen that, despite setting a criterion (see Table 4.1) that suitable research should be reported in English, research has fortunately not been limited to Anglophone countries. Nevertheless concepts among students in developing countries have been under-researched.
As different acid-base models are taught at different stages in a student’s career, it was also important to analyse the distribution of educational levels among research cohorts. The research studies were grouped according to levels familiar in South Africa where a child enters Grade 1 when 6 or 7 years old (Table 5.6).
Table 5.6 Educational levels of student cohorts
Educational level
of students Explanation of level
*Numbers of reports
Elementary Up to Grade 7, natural science students 2
Junior secondary Grades 8 & 9, natural science students who have not yet chosen a chemistry elective 10
Senior secondary Grades 10 to 13, 24
Tertiary Undergraduate or honours programmes in chemistry (including pre-service teachers) 8 Teachers (including
pre-service)
Teaching at any school level 4
Postgraduate Masters or doctoral students in chemistry 2
Experts University teaching staff 2
* Total is more than 41 because several studies compared conceptions across ages and tertiary students included pre- service teachers.
From this data it can be seen that research has included all levels of education, although not equally. The most commonly studied age group are senior secondary students. Twenty four reports on this age group indicates considerable research which could focus on conceptions of the Arrhenius and Brønsted acid-base models, as outlined in Section 3.3, for critical analysis.
Possible origins of these conceptions among more junior students and their implications among tertiary students have also received some attention. Conceptions of pre-service teachers have two impacts. Firstly it indicates problems which undergraduate programmes need to address.
Furthermore it indicates conceptions which may be transmitted to future students (see Section 2.3.4). Hence I have included pre-service teachers twice, and it appears these have received little attention. In brief, high school student conceptions have received considerable attention but those arising earlier or the implications of these later have been under-researched.
Research aims were analysed next, in order to understand the nature of research already carried out. These are shown individually in Table 5.1 where it can be seen that some research reports included more than one aim. In summary, 68% of the reports aimed to investigate the nature of student conceptions, with 17% of the total considering the source of these conceptions.
Variation of conceptions with time among the same cohort was a stated aim for 24% of the reports. These longitudinal studies were either before and after interventions, or immediately after teaching and then some time later, so considering retention of the learning. Comparisons across ages were covered by 10% of the reports. A few reports also investigated prevalence of alternative conceptions in a cohort (2%) or achievement levels of students on conceptual questions (5%). Quantitative data from such studies was largely irrelevant in the current study.
With two thirds of the research reports having a stated aim of investigating the nature of student conceptions, the body of work was then likely to be a rich source of data on the conceptions.
The particular topics in which student conceptions had been sought are summarised below in Table 5.7. Most topics included in high school acid-base curricula have been considered by the body of research. However few studies have included salts, heat of reaction, indicators, conjugate pairs or polyprotic acids. From this uneven distribution it can be expected that there would be sufficient research in some topics to achieve accurate descriptions of difficulties, while in others analysis would identify specific research gaps.
Table 5.7 Acid-base topics included in research on student conceptions
Acid-base topic
Number of reports
on conceptions Acid-base topic
Number of reports on conceptions
Definitions 13 Everyday applications 14
Neutralization 24 Formulae 9
pH 24 Aqueous equilibria 11
Salts 4 Acid-base strength 16
Macroscopic properties 10
Indicators 5
Brønsted acid-base conjugates
6
Heat of reaction 3 Polyprotic acids 5
From all these analyses, in answer to research sub-question 1b, the scope of the research is dominated by high-school cohorts in countries across much of the world, who speak many different languages. There is a deficiency of research on students in developing countries and among teachers, and elementary or tertiary students. The nature of student conceptions has been researched for a range of acid-base topics in accordance with this being the most common research aim.