1. Investigating the potential for unanticipated consequences of teaching the tentative nature of science
William W. Cobern
Betty AJ Adams
Brandy A-S Pleasants
Andrew Bentley
Robert Kagumba
The Mallinson Institute
for Science Education
Western Michigan University
Kalamazoo, MI
The University of Northern Colorado
Greeley, CO
Delta State University
Cleveland, MS

2. Climate change science?
Evolution?
Certain science theories, such as evolution and anthropogenic climate change, are rejected by significant portions of the public.
Climate change science?
Settled science or
“just theories”?
Sometimes these scientific ideas are criticized as “just theories,” with the implication that the ideas are speculative and should not be trusted as if they represent accurate knowledge.

3. Are we science educators faultless?
The editor at Nature thinks not:
Perhaps a more pressing criticism of the way NOS is taught in schools is that it encourages rather too much doubt over scientific ideas. Many findings, after all, are well established and, indeed, taken as such by professional scientists who use them as shoulders to stand on. Not all science is tentative, and researchers should not be shy about saying so — both to those in schools and to those in charge of schools. (Nature, 2017, p. 149)

4. Teaching the tentative nature of scientific knowledge is an important element of science education; however…
It is a reasonable conclusion from the inherently tentative nature of science that evolution or climate change ideas are just that, tentative.
To what extent does focusing on the tentative nature of science inadvertently undermine confidence in science?

5. Bearing in mind the “just a theory” argument,
we considered that students who oppose or
who are uncomfortable with controversial
science concepts may bolster their doubts by
turning to the inherently tentative nature of science.

6. Initial and replication exploratory studies
preservice K-8 teacher education students
large Midwestern public university
demographic and Likert survey items, plus comments section

7. Study initially tested two hypotheses
Hypothesis 1: Students have confidence in the veracity of scientific concepts even if they have doubts about some areas of science such as evolution and climate change.
Hypothesis 2: Students less confident about the veracity of controversial concepts are likely to be more confident that scientific knowledge is tentative.

8. Study Design and Instrumentation
Survey of student confidence in…
uncontroversial scientific concepts  Newton’s First Law  heart/lung function
controversial scientific concepts  human evolution  anthropogenic climate change
the nature of science as durable yet tentative

9. The items were all cast in a Likert format followed by a space for comments.
For example:  
Please read the following scientific statement. Using the scale below, indicate how confident you are that the scientific statement is true. In the space below, briefly explain your choice of confidence level.
According to the science community, an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
Not at all confident Very confident

10. Nature of science item – initial study 2015
According to the science community, scientific knowledge
is durable, but can change in light of new evidence
or changes in perspective.
is durable, but can change in light of new evidence
or changes in perspective.
Nature of science items – replication study 2017
…is accurate and
can be trusted.
…can change in the light of new evidence or changes in perspective.

11. Analyses
We began by exploring the quantitative data using simple statistics (comparisons of means and correlations).
Comments made by students were categorized with respect to their confidence in scientific ideas in balance with their confidence in the durable yet inherently tentative nature of science.

12. Findings
Hypothesis 1: Students have confidence in the veracity of scientific concepts even if they have doubts about some areas of science such as evolution or climate change.

13. Difference in confidence means between 2015-2017 Year N Mean SD
Year N
Mean SD
Motion
2015
297
4.48
.78
2017
202
4.49
.79
Heart
301
3.76
1.24
199
3.67
1.21
Evolution
298
4.19
1.01
201
4.11
1.10
Warming (climate change)
303
3.89*
.99
4.08*
.95
Science durable but can change
296
4.42**
.84
Science accurate & can be trusted
195
3.37**
1.09
Science can change
194
4.73**
.54
* Difference is significant at the 0.05 level (2-tailed). ** Difference is significant at the 0.01 level (2-tailed).

14. Difference in confidence means between 2015-2017
Year N
Mean SD
Science durable but can change
2015
296
4.42**
.84
Science accurate & can be trusted
2017
195
3.37**
1.09
Science can change
194
4.73**
.54
** Difference is significant at the 0.01 level (2-tailed).
Between 2015 and 2017, the word “durable” was removed from the item regarding the tentative, changeable nature of science.
Reported confidence rose significantly for the simplified statement that “…scientific knowledge can change…”

15. Difference in confidence means between 2015-2017
Year N
Mean SD
Science durable but can change
2015
296
4.42**
.84
Science accurate & can be trusted
2017
195
3.37**
1.09
Science can change
194
4.73**
.54
** Difference is significant at the 0.01 level (2-tailed).
The most surprising result from 2017 was how low students rated their confidence in the accuracy and trustworthiness of science…
a precipitous and statistically highly significant drop from the composite item used in 2015 that mentioned durability (t( *)=11.396, p<0.001).

16. Findings
Hypothesis 2: Students less confident about the veracity of controversial concepts are likely to be more confident that scientific knowledge is tentative.
Comparing NOS confidence means between groups with low and high confidence in controversial science statements N
Min
Max
Mean SD
Evolution
Low (1, 2) confidence
2015 Science durable but can change 20 1 5
4.25
1.07
2017 Science accurate & trustworthy 19
2.89
1.10
2017 Science can change 3
4.68
.58
High (4, 5)
confidence
236
4.44
.84
150
3.44
1.09
149 2
4.74
.55

17. Current conclusions
It appears most students have high confidence in the tentative, changeable nature of scientific knowledge, and it does not seem to have an inverse relationship with confidence in controversial science.
However, the bad news is that students’ confidence in the accuracy or trustworthiness of scientific knowledge is lower than expected, irrespective of their confidence in evolution and climate change science.
When durability is expressed as “accurate and can be trusted” and this concept is separated from the tentative nature of science, confidence in the trustworthiness of scientific knowledge drops across the board.

18. Future work
In existing data, we are analyzing qualitative comments and also looking at correlations between survey responses and demographic factors.
We are in the process of exploring how preservice k-8 college students interpret the idea that scientific knowledge is “durable,” and we are considering additional semantic issues more closely (e.g., “theory,” “accurate,” “trusted,” “true”)
We will run a replication of the 2017 study, again using disaggregated NOS trustworthy/tentative items to test/validate current conclusions.

19. THANK YOU
For a copy of our preliminary report and for information about our research… contact Bill Cobern at

20. THANK YOU
For a copy of our preliminary report and for information about our research… contact Bill Cobern at

21. THANK YOU
For a copy of our preliminary report and for information about our research… contact Bill Cobern at