But is it effective?

Assessing the impact of a historically based unit

David W. Rudge, Biological Sciences & The Mallinson Institute for Science Education, Western Michigan University

Uric C. Geer, The Mallinson Institute for Science Education, Western Michigan University

Eric M. Howe, Department of Education, Assumption College

Outline

• I. Introduction

• II. Method

• III. Results

• IV. Conclusions

I. Introduction

• The Phenomenon of Industrial Melanism

Biston betularia f. typical

Biston betularia f. carbonaria

I. Introduction• The Phenomenon of Industrial Melanism

Frequency of dark form Centers of air pollution

I. Introduction• The Phenomenon of Industrial Melanism

Photographs of light and dark forms on soot-darkened and lichen-covered tree trunks

I. Introduction

• History of Research on Industrial Melanism

• Mystery Phenomenon format

• Exploration from multiple theoretical perspectives

Lamarckian Inheritance

Natural Selection

Mutation Theory

I. Introduction

• Did the Mystery Phenomenon unit improve student understandings of a targeted set of issues associated with the nature of science?

• If so, what was it about the unit that led to these changes?

Research Questions

II. Method1. Participants

2. Context

3. Intervention

4. Procedure

5. Data Analysis

1. Participants

• Conducted at large Midwestern university • Spring 2007• Preservice elementary school teachers • 13 participants (19 potential)• 100% white, female, 18-30 yrs. old

2. Context• Based on Michigan Science Curriculum Framework,

AAAS Project 2061, National Science Education Standards

• BIOS 1700 Life Science for Elementary Educators I– Taxonomy, Anatomy and Physiology, Ecology,

Evolution• Taught in lecture-lab (24 students) format• Unit of interest takes place during lab

3. Intervention• Open-ended problems from history of research on

industrial melanism– Instructor provides information that historically led to

discovery– Students are invited to identify problem, pose theories – Students are invited to come up with ways to test theories

• Instructor facilitates Explicit / Reflective† discussion: Explicit

• NOS is actively considered in relation to content Reflective

• Students construct their own insights

† cf. Abd-El-Khalick & Lederman (2000)

4. ProcedureQualitative (Interpretive) Research

1. Pre/post test = open-ended VNOS-C

survey

2. Semi-structured interviews††

- To establish validity of survey- To allow further probing of student responses

††Lederman & O’Malley, 1990

4. ProcedurePre- and Post- Survey NOS Topics1. Definition of theories, how created

2. Whether theories change

3. Definition of experiments

4. Whether experiments are necessary

5. The subjective (theory laden) nature of science

6. Role of imagination and creativity

5. Data Analysis• Characterize pre- and post- responses to questions into emergent themes

– cross check consistency with rest of students answers

• To address whether change has occurred-analyze aggregate for evidence of change

• To address why change has occurred-analyze responses of interviewed individuals

III. ResultsSummary of Change in Student’s NOS Views (N=11)

Presurvey Postsurvey

Naïve More informed

Naïve More informed

1. Nature of theories n = 2

18%

n = 4

36%

2. Possibility of theory change

n = 3

27%

n = 0

0%

3. Necessity of experiments

n = 0

0%

n = 9

81%

6. Creativity and Imagination

n = 4

36%

n = 2

18%

III. ResultsStudent Interview re. Necessity of Experiments

“The only thing that jumps out I guess is initially before I had it in my mind that something had to be tested and basically you had to have proof. So therefore you had to do an experiment and prove that this theory or this idea is true. Whereas in this, when I went back in after we talked about it in class, you know sometimes we can’t always do experiments. So it changed my idea that- OK wait a second here, if we can’t do experiments what do we do? You know, how do we prove stuff? And then it went back to the case where we kind of dipped into, you know, we have to rely on historic history–historical information, you know. It’s still research, it’s still … it’s still finding information but it’s not a step by step process of hands-on trying something out. It’s more taking other ideas from other past experiments or experiences that other scientists have had and making them your own.” (Student 29-1, interview)

IV. Conclusions

• The Mystery Phenomenon Unit did cause some change in student understandings of a targeted set of NOS issues.

• Whether this is due to the use of history is somewhat unclear.

Acknowledgements

This material is based on work supported by the National Science Foundation under Grant No. 0202923. Any opinions, findings and conclusions or recommendations expressed in this material are those of the authors(s) and do not necessarily reflect the views of the National Science Foundation.