FROM CONTEXT TO CONCEPT: THE IMPLICATIONS FOR THE TEACHING OF CHEMISTRY

 

Warren Beasley

School of Education, The University of Queensland, Australia

w.beasley@mailbox.uq.edu.au

 

The beginning of teaching should be made by dealing with actual things. The object must be a real, useful thing, capable of making an impression upon the senses… if visible, with the eyes; if audible, with the ears; if tangible, with the touch; if odorous, with the nose; if sapid, with the taste.  First the presentation of the thing itself … then the real explanation for the further elucidation of it

(J.A. Comenius, 1592-1670)

 

Introduction

The challenge to teach in context and for students subsequently to learn in context is an emerging challenge for chemistry teachers [1-2].  The paradigm shift underlying this innovation in design requires radical changes in teacher and student actions for the taught, learned and assessed curriculum [3].  A 180-degree change in teacher and student behaviour is necessary for the syllabus to be implemented in the spirit to which it is intended.

 

Essentially the learning settings will require a change from

 

A CONCEPT TO CONTEXT APPROACH 

TO

 A CONTEXT TO CONCEPT APPROACH 

Associated with this radical change in pedagogy is a very different balance of student assessment instruments that are required to meet different outcomes. The balance is now very much in favour of student investigations (Scientific and Non-Scientific) evolving out of focus questions generated from face-to-face interactions with the school-generated contexts. This paper analyses the challenges facing teachers and students in teaching and learning in context.

 

The meaning of “context”

Syllabuses use ‘context’ to mean “a group of related situations, phenomena, technological applications and social issues”.

 

Examples of contexts adopted by Queensland teachers are:

Drugs, Medicine and People; The Air We Breathe; Fertilisers and Pesticides; Choosing the Right Material, Forensic Chemistry, The Health of Our River, The Manufacture and Analysis of Beer, Wine & Spirits, The Sugar Cane Industry, Marine Chemistry, Metals and Mining, The Air We Breathe.

 

Underlying assumptions about content of contemporary syllabuses

A syllabus in its broadest sense reflects a hypothesis about learning — what is worth learning and how it should be learned and assessed, and as such reflects the deep-seated values and beliefs of the designers.  With these particular syllabuses one can recognise the following changes in emphases [4].

 

Less emphasis on

 

More emphasis on

Knowing scientific facts and information

Understanding scientific concepts and developing abilities of inquiry

 

Studying subject matter of disciplines

Learning subject matter in the context of inquiry, technology, science in personal and social perspectives, and history and nature of science

 

Separating science knowledge and science content

 

Integrating all aspects of science content

Covering many science topics

Studying a few fundamental science concepts

 

Implementing inquiry as a set of processes

Implementing inquiry as instructional strategies, abilities, and ideas to be learned

 

 

Concept-based design

In this model, science is transmitted to students as discipline-based knowledge that has its worth (for students) in its contribution to a tertiary entrance score.  Recent studies into science teaching in Australia report that “teacher talk” remains the dominant teaching strategy [5].  Transmission of scientific knowledge devoid of a meaningful framework of student experience or prior knowledge is the predominant teacher behaviour.  Such a model of science teaching has resulted in the application of scientific theory as an optional infrequent experience for students.  When a context is introduced it is often done superficially through exercises and usually occurs at the end of an instructional sequence if time, interest or teacher knowledge permit. 

 

This model of teaching in science classrooms can be illustrated as follows:

 

 

 

Figure 1. A model of teacher transmission of content in science classrooms

 

Context-based design

The starting point for the design of units of work by schools is the selection of an appropriate context.  This context and the concept map surrounding it are expected to lead to meaningful questions that will focus student investigations and other learning experiences in the unit.  This decision is only constrained by teacher interest and expertise, access to resources for investigations, the conceptual underpinning of the context, and the time required.

 

The design encourages teachers and students to develop an understanding of these key concepts on a ‘need-to-know’ basis.  The context as initially revealed at the beginning of a unit remains central to the classroom processes and specific conceptual development becomes important when student uncertainty hinders further elucidation of meaningful knowledge and skills.

 

This approach requires teachers to engage students in authentic real-world experiences of the context as the starting point for student learning [6].  In doing so the model requires that initially the context be elaborated by building up a concept map about the context.  At the centre of this map is the context surrounded by a circle of issues, features or events associated with the context.  Further out the associated science processes, models, topics, and science concepts are represented.

 

These elements in the chemistry syllabus can be connected in the manner represented in Figure 2.

 

 

Figure 2.  The relationship between the elements of a unit of work

 

The following flowchart (Figure 3) outlines the major steps in the design of a unit of chemistry commencing with the context being revealed, through to the finalisation of learning as evidenced in student presentations and reports.

 

Comparison of the learning sequences diagrammed in Figures 1 & 3, soon reveals that a radical change in classroom pedagogy is required.  The challenges for both teachers and students to act differently are substantial and will require a period of sustained professional development opportunities.

  


 

Figure 3. Context-based unit of work flowchart

 

Teaching to a Contextually Based Curriculum Design

This approach requires acceptance by teachers of the context as the starting point for student learning of science.  Within that context intelligent questions need to be raised in the minds of students so as to create an investigative framework for further student activities.  The syllabus objectives such as conceptual understanding, investigative skills, and complex reasoning still remain the target outcomes; and are systematically developed as a consequence of a student’s activities that are driven by a ‘need-to-knowstimulus.  In seeking the answers to the focus questions that are introduced at the beginning of a unit of work students are guided by a framework of investigations and conceptual knowledge to defensible decisions about the original questions.

 A paradigm shift in teachers thinking and action will be required so as to allow opportunities for meaningful student learning within a ‘teaching in contextparadigm to be created.  This shift can be exemplified by an analysis of a Unit from the “Chemistry in the Community curriculum produced by the American Chemical Society for high school classrooms [7].  This curriculum provides the resources for teachers to implement a learning in context approach.  These resources were developed and trailed in the 1980’s and a fourth edition was released in 2001.

The Unit is titled ‘Supplying Our Water Needs and the context is a fish kill in the community reservoir.  The investigation that follows leads students (albeit citizens) to an understanding of the key implications of the chemistry of water.  The content sequence for the unit is:

 

1.  The quality of our water

2.  A look at water and its contaminants

3.  Investigating the cause of the fish kill

4.  Water purification and treatment

5.  Putting it all together:  Fish kill in Riverwood — Who pays?

 

Student investigations, motivated by a ‘need-to-know’ stimulus, of the cause of the fish kill require the following chemistry knowledge and skills to be developed:

 

1.  Solubility

2.  Solution concentration

3.  Oxygen supply and demand

4.  Temperature and gas solubility

5.  You decide: Too much oxygen or too little?

6.  Acid contamination

7.  Ions and ionic compounds

8.  Heavy metal contamination

9.  You decide: Did heavy metal ions kill the fish?

10.  Molecular substances in the river

 

The other seven Units that make up this resource for high school chemistry students are:

 

·       Conserving Chemical resources

·       Petroleum: To Build or to Burn?

·       Understanding Foods

·       Nuclear Chemistry in our World

·       Chemistry, Air and Climate

·       Chemistry and Health

·       The Chemical Industry: Promise and Challenge

 

These topics represents eight different contexts for which students already have a level of recognition and science understanding by virtue of their prior life experiences as well as ten years of science education in the primary and middle years of schooling.  It should be emphasized and understood that this approach to learning science is not about “dumbing down” science course outcomes.  It represents an approach to curriculum design that is more consistent with accepted models of learning and teaching. 

Another distinct advantage of this context-centred approach is the deliberate development of student abilities in the area of complex reasoning.  Complex reasoning is interpreted to be the combination of problem solving, critical thinking and decision-making.  Classroom experiences very rarely gave students the chance to develop such attributes.  Student performance on more difficult quantitative problems became the default mechanism for the demonstration of critical thinking and/or decision-making.

A context centred approach does offer teachers an opportunity to develop such highly regarded outcomes as students’ complex reasoning from a platform of scientific investigative skills and conceptual knowledge.  Teachers need to be prepared to commence students’ learning opportunities in a meaningful context within a societal dimension that raises worthwhile questions in the minds of students.  The pathways to complex reasoning become more transparent for students and teachers alike.  The unit on water outlined above illustrates the pathway of conceptual understanding and investigative skills leading to the critical thinking and decision-making needed to satisfy the demands in the final section Putting it all together:  Fish kill in Riverwood — Who pays?   

These higher order cognitive skills are not an afterthought in the curriculum design.  They are integral to the development of the unit and as such give students valuable learning experiences.  Such experiences are repeated throughout the eight units.

 

Student roles during classroom change

The roles of students in educational change is often ignored or taken for granted during periods of educational innovation.  Teachers and administrators have been the main beneficiary of professional development programs that aim at the behavioural change of adults in the workplace.  The underlying assumption has been that students will be passive recipients of the actions of teachers and will be able to modify their behaviours and beliefs about learning accordingly.  It is the ‘student as technician’ model all over again that is known not to work for their teachers.  These assumptions contradict much of what is now understood about learning in workplace settings where all the participants need developmental assistance to grow professionally to cope with changes in workplace practices [8].

Osborne and Freybergh [9] observed major differences between the teacher’s intentions and the student learning which was actually taking place in science classrooms.  It was postulated that this difference was the direct result of a number of disparities:

 

 

In a more general sense the literature concerning student roles during the implementation of change in school settings indicates that:

 

Students, like their teachers, will need to learn in a socially constructivist manner about how to learn within this new paradigm for senior science education. In designing for these opportunities teachers will also need to demonstrate their commitment to social constructivist designs.  These designs emphasise the rich and complex learning that can be achieved by reflecting together on personal experiences in a shared course.

 

The challenges ahead

One can judge the degree of teacher change that is necessary to do justice to such an innovation by reference to the following equations:

            Old Content + Old Pedagogy = No Change

 

            Old Content + New Pedagogy = Mild Change

 

            New Content + Old Pedagogy = Mild Change

 

            New Content + New Pedagogy = Radical Change

Curriculum designs for context-based learning in chemistry requires a fundamentally different approach to content selection, teaching strategies and assessment instruments.  It therefore requires a radical change in approach to teaching and to learning.  Such a change is considered desirable if we are to make the learning of chemistry/physics more meaningful and more enjoyable for students, and to open chemistry/physics to a new group of students by:

 

·       Placing chemistry/physics in a societal context

·       Cultivating scientific inquiry skill

·       Cultivating decision-making skills

·       Using chemistry/physics to understand socio-technological problems

·       Demonstrating the inter-relationships among the sciences

 

A complete paradigm shift in teachers thinking, content knowledge and praxis needs to accompany the implementation of these new curriculum models.

Much is now understood about the attributes of teacher change required to implement educational innovation such as this new syllabus design.  The key lies in the nature of the professional development [10] that will be needed to accompany such innovation as well as the resources that are made available to satisfy the appetites of such change.  Although the planned change is systemic in its intent, large-scale change must be implemented locally i.e. in an individual teacher’s classroom.

It is only when the

 

Rate of Professional Development   >  Rate of the Change of the Teaching Context

that authentic change in teacher behaviour is achieved.

Curriculum innovation provides a never-ending tension in educational work settings and this tension must be addressed in the context of teachers’ ongoing work.  Professional development models, to be effective, need to be informed by current insights into workplace and adult learning principles so that fundamental changes in practice are attainable.  Action learning approaches [11-12] offer a mechanism for such insights to be adopted in future professional development initiatives.

 

References

1.  Lye, H., Fry, M. & Hart, C. (2001) What does it mean to teach physics ‘in context’? Australian Science Teachers Journal, 48(1), 16-22.

2.  Whitelegg, E. & Parry, M. (1999) Real-life contexts for learning physics: meanings, issues and practice. Physics Education, 34(2), 68-72

3.  Beasley, W.F., Butler, J.E. and Satterthwait, D. (1993). Senior Sciences Future Direction Project. (Final Report). Board of Senior Secondary School Studies, 127 pp, February.

4.  National Research Council (1996). National Science Education Standards, Washington DC: National Academy Press.

5.  Goodrum, D, Hackling, M. & Rennie, L. (2001). Research Report: The status and quality of teaching and learning of science in Australian schools. Canberra; Department of Education, Training and Youth Affairs

6.  Anthony, S., Mernitz, H., Spencer, B. & Gutwill, J. (1998) The ChemLinks and ModularChem Consortia: Using active and context-based learning to teach students how chemistry is actually done. Journal of Chemical Education, 75(3), 322-324.

7.  American Chemical Society (2001). Chemistry in the Community, 4th Edition (H.W. Heikkinen, Ed), New York: Freeman.

8.  Butler, J. (1996). Professional Development: Practice as Text, Reflection as Process and Self as Locus. Australian Journal of Education, 40(3), 265-283

9.  Osborne, R. and Freyberg, P (1985). Learning in Science - The implications of Children’s Science, Auckland: Heinemann.

10.  Butler, J. (1992) Teacher professional development; an Australian case study. Journal of Education for Teaching, 18(3), 221-238.

11.  McGill, I. and Beaty, L. (1993) Action Learning: A Practitioner's Guide. London: Kogan Page.

12.  Kemmis, S. and McTaggart, R. (1988) The Action Research Planner. (Deakin: Deakin University).