Download he noticed warmth

Magic moments in scientific inquiry: What biology teacher
students should know about this topic
Conference on the International Meeting of Science Teacher
Dirk Krüger
Freie Universität Berlin
Institute of Biology Education
Outline
Definition of competence
Conceptual framework for competencies in the scientific methodology
How to develop competence in scientific inquiry: topic photosynthesis
Studies in biology education - results
Example out of the topic cutaneous respiration
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
2
Competence
Definition of competence according to F. E. Weinert:
Competences are available or learnable cognitive abilities and talents, for
solving certain problems, as well as the associated motivational, volitional and
social readiness and abilities, for solving problems in variable situations
successfully and responsibly.
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
3
Conceptual Framework for Competences in
the Scientific Methodology
Mayer 2007
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
4
Students Competencies: Scientific Inquiry
Students are able
- to distinguish between a scientific question and an hypothesis
- to design simple experiments,
- to perform simple experiments and/or evaluate them,
- to use the results of the experiment to explain cause-andeffect relations.
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
5
Photosynthesis – a topic with many school experiments!
Experiment according to William L. Potts (1920)
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
6
Example: topic photosynthesis
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
7
Possible reactions
- to ask a question
- to propose a hypothesis
- (to refer to theories)
- to plan investigations
- to make observations
- (to collect data)
- to draw conclusions
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
8
Questions – hypotheses
Question
How did he discover the plant that had been exposed to light?
Hypotheses
stochastical theories
he made a guess
physical theories
he noticed warmth
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
psychological theories
people favor a special order
people favor a color
people look at the selected plant
Dirk Krüger
Magic moments in scientific inquiry
pragmatische Theorien
he looked through a
windows/keyhole/uses a
video camera
the plant was moved from its
place
There is somebody in the
room who helps him
esoterische Theorien
he has extrasensory power
13.08.2009
9
Questions – hypotheses
Question
How did he discover the plant that had been exposed to light?
Hypotheses
stochastical theories
he made a guess
physical theories
he noticed warmth
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
psychological theories
people favor a special order
people favor a color
people look at the selected plant
Dirk Krüger
Magic moments in scientific inquiry
pragmatische Theorien
he looked through a
windows/keyhole/uses a
video camera
the plant was moved from its
place
There is somebody in the
room who helps him
esoterische Theorien
he has extrasensory power
13.08.2009
10
Questions – hypotheses
Question
How did he discover the plant that had been exposed to light?
Hypotheses
stochastical theories
he made a guess
physical theories
he noticed warmth
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
psychological theories
people favor a special order
people favor a color
people look at the selected plant
Dirk Krüger
Magic moments in scientific inquiry
pragmatische Theorien
he looked through a
windows/keyhole/uses a
video camera
the plant was moved from its
place
There is somebody in the
room who helps him
esoterische Theorien
he has extrasensory power
13.08.2009
11
Questions – hypotheses
Question
How did he discover the plant that had been exposed to light?
Hypotheses
stochastical theories
he made a guess
physical theories
he noticed warmth
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
psychological theories
people favor a special order
people favor a color
people look at the selected plant
Dirk Krüger
Magic moments in scientific inquiry
pragmatische Theorien
he looked through a
windows/keyhole/uses a
video camera
the plant was moved from its
place
There is somebody in the
room who helps him
esoterische Theorien
he has extrasensory power
13.08.2009
12
Questions – hypotheses
Question
How did he discover the plant that had been exposed to light?
Hypotheses
stochastical theories
he made a guess
physical theories
he noticed warmth
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
psychological theories
people favor a special order
people favor a color
people look at the selected plant
Dirk Krüger
Magic moments in scientific inquiry
pragmatische Theorien
he looked through a window/
keyhole/uses a video camera
the plant was shifted from its
place
there is somebody in the room
who helps him
esoterische Theorien
he has extrasensory power
13.08.2009
13
Questions – hypotheses
Question
How did he discover the plant that had been exposed to light?
Hypotheses
stochastical theories
he made a guess
physical theories
he noticed warmth
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
psychological theories
people favor a special order
people favor a color
people look at the selected plant
Dirk Krüger
Magic moments in scientific inquiry
pragmatische Theorien
he looked through a windows/
keyhole/uses a video camera
the plant was moved from its
place
there is somebody in the room
who helps him
esoterische Theorien
he has extrasensory power
13.08.2009
14
Questions – hypotheses
Question
How did he discover the plant that had been exposed to light?
Hypotheses
stochastical theories
he made a guess
physical theories
he noticed warmth
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
psychological theories
people favor a special order
people favor a color
people look at the selected plant
Dirk Krüger
Magic moments in scientific inquiry
pragmatische Theorien
he looked through a windows/
keyhole/uses a video camera
the plant was shifted from its
place
there is somebody in the room
who helps him
esoterische Theorien
he has extrasensory power
13.08.2009
15
Questions – hypotheses
Question
How did he discover the plant that had been exposed to light?
Hypotheses
stochastical theories
he made a guess
physical theories
he noticed warmth
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
psychological theories
people favor a special order
people favor a color
people look at the selected plant
Dirk Krüger
Magic moments in scientific inquiry
pragmatische Theorien
he looked through a window/
keyhole/uses a video camera
the plant was shifted from its
place
there is somebody in the room
who helps him
esoterische Theorien
he has extrasensory power
13.08.2009
16
Questions – hypotheses
Question
How did he discover the plant that had been exposed to light?
Hypotheses
stochastical theories
he made a guess
physical theories
he noticed warmth
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
psychological theories
people favor a special order
people favor a color
people look at the selected plant
Dirk Krüger
Magic moments in scientific inquiry
pragmatische Theorien
he looked through a window/
keyhole/uses a video camera
the plant was shifted from its
place
there is somebody in the room
who helps him
esoterische Theorien
he has extrasensory power
13.08.2009
17
Questions – hypotheses
Question
How did he discover the plant that had been exposed to light?
Hypotheses
stochastical theories
he made a guess
physical theories
he noticed warmth
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
psychological theories
people favor a special order
people favor a color
people look at the selected plant
Dirk Krüger
Magic moments in scientific inquiry
pragmatische Theorien
he looked through a window/
keyhole/uses a video camera
the plant was shifted from its
place
there is somebody in the room
who helps him
esoterische Theorien
he has extrasensory power
13.08.2009
18
Questions – hypotheses
Question
How did he discover the plant that had been exposed to light?
Hypotheses
stochastical theories
he made a guess
physical theories
he noticed warmth
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
psychological theories
people favor a special order
people favor a color
people look at the selected plant
Dirk Krüger
Magic moments in scientific inquiry
pragmatical theories
he looked through a window/
keyhole/uses a video camera
the plant was shifted from its
place
there is somebody in the room
who helps him
esoterische Theorien
he has extrasensory power
13.08.2009
19
Questions – hypotheses
Question
How did he discover the plant that had been exposed to light?
Hypotheses
stochastical theories
he made a guess
physical theories
he noticed warmth
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
psychological theories
people favor a special order
people favor a color
people look at the selected plant
Dirk Krüger
Magic moments in scientific inquiry
pragmatical theories
he looked through a window/
keyhole/uses a video camera
the plant was shifted from its
place
there is somebody in the room
who helps him
esoterical theories
he has extrasensory power
13.08.2009
20
Design of an experiment
Design and/or Performance
physical theories
he noticed warmth
students test by themselves
repetition, without allowance to feel
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
students test by themselves
repetition, without allowance to feel
psychological theories
people favor a special order
people favor a color
people look at the selected plant
many repetitions
repetition, only some people look at the
plant or
Take their eyes off the plant
Dirk Krüger
Magic moments in scientific inquiry
stochastical theories
he makes a guess
many repetitions
pragmatical theories
he looked through a window/
keyhole/used a video camera
the plant was shifted from its place
repetition, somebody
accompanies him, all plants were
moved
somebody assists him
dismiss pot. assistant as well, to
blindfold him, …
esoterical theories
he has extrasensory power
no design possible!
13.08.2009
21
Design of an experiment
Design and/or Performance
physical theories
he noticed warmth
students test by themselves
repetition, without allowance to feel
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
students test by themselves
repetition, without allowance to feel
psychological theories
people favor a special order
people favor a color
people look at the selected plant
many repetitions
repetition, only some people look at the
plant or
Take their eyes off the plant
Dirk Krüger
Magic moments in scientific inquiry
stochastical theories
he makes a guess
many repetitions
pragmatical theories
he looked through a window/
keyhole/used a video camera
the plant was shifted from its place
repetition, somebody
accompanies him, all plants were
moved
somebody assists him
dismiss pot. assistant as well, to
blindfold him, …
esoterical theories
he has extrasensory power
no design possible!
13.08.2009
22
Design of an experiment
Design and/or Performance
physical theories
he noticed warmth
students test by themselves
repetition, without allowance to feel
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
students test by themselves
repetition, without allowance to feel
psychological theories
people favor a special order
people favor a color
people look at the selected plant
many repetitions
repetition, only some people look at the
plant or
Take their eyes off the plant
Dirk Krüger
Magic moments in scientific inquiry
stochastical theories
he makes a guess
many repetitions
pragmatical theories
he looked through a window/
keyhole/used a video camera
the plant was shifted from its place
repetition, somebody
accompanies him, all plants were
moved
somebody assists him
dismiss pot. assistant as well, to
blindfold him, …
esoterical theories
he has extrasensory power
no design possible!
13.08.2009
23
Design of an experiment
Design and/or Performance
physical theories
he noticed warmth
students test by themselves
repetition, without allowance to feel
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
students test by themselves
repetition, without allowance to feel
psychological theories
people favor a special order
people favor a color
people look at the selected plant
many repetitions
repetition, only some people look at the
plant or
take their eyes off the plant
Dirk Krüger
Magic moments in scientific inquiry
stochastical theories
he makes a guess
many repetitions
pragmatical theories
he looked through a window/
keyhole/used a video camera
the plant was shifted from its place
repetition, somebody
accompanies him, all plants were
moved
somebody assists him
dismiss pot. assistant as well, to
blindfold him, …
esoterical theories
he has extrasensory power
no design possible!
13.08.2009
24
Design of an experiment
Design and/or Performance
physical theories
he noticed warmth
students test by themselves
repetition, without allowance to feel
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
students test by themselves
repetition, without allowance to feel
psychological theories
people favor a special order
people favor a color
people look at the selected plant
many repetitions
repetition, only some people look at the
plant or
take their eyes off the plant
Dirk Krüger
Magic moments in scientific inquiry
stochastical theories
he makes a guess
many repetitions
pragmatical theories
he looked through a window/
keyhole/used a video camera
the plant was shifted from its place
repetition, somebody
accompanies him, all plants were
moved
somebody assists him
dismiss pot. assistant as well, to
blindfold him, …
esoterical theories
he has extrasensory power
no design possible!
13.08.2009
25
Design of an experiment
Design and/or Performance
physical theories
he noticed warmth
students test by themselves
repetition, without allowance to feel
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
students test by themselves
repetition, without allowance to feel
psychological theories
people favor a special order
people favor a color
people look at the selected plant
many repetitions
repetition, only some people look at the
plant or
take their eyes off the plant
Dirk Krüger
Magic moments in scientific inquiry
stochastical theories
he makes a guess
many repetitions
pragmatical theories
he looked through a window/
keyhole/used a video camera
the plant was shifted from its place
repetition, somebody
accompanies him, all plants were
moved
somebody assists him
dismiss pot. assistant as well, to
blindfold him, …
esoterical theories
he has extrasensory power
no design possible!
13.08.2009
26
Design of an experiment
Design and/or Performance
physical theories
he noticed warmth
students test by themselves
repetition, without allowance to feel
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
students test by themselves
repetition, without allowance to feel
psychological theories
people favor a special order
people favor a color
people look at the selected plant
many repetitions
repetition, only some people look at the
plant or
take their eyes off the plant
Dirk Krüger
Magic moments in scientific inquiry
stochastical theories
he makes a guess
many repetitions
pragmatical theories
he looked through a window/
keyhole/used a video camera
the plant was shifted from its place
repetition, somebody
accompanies him, all plants were
moved
somebody assists him
dismiss potential assistant as
well, to blindfold him, …
esoterical theories
he has extrasensory power
no design possible!
13.08.2009
27
Design of an experiment
Design and/or Performance
physical theories
he noticed warmth
students test by themselves
repetition, without allowance to feel
biological theories
the color of the leaves/phyllotaxy changed
the odor changed
he noticed oxygen
students test by themselves
repetition, without allowance to feel
psychological theories
people favor a special order
people favor a color
people look at the selected plant
many repetitions
repetition, only some people look at the
plant or
take their eyes off the plant
Dirk Krüger
Magic moments in scientific inquiry
stochastical theories
he makes a guess
many repetitions
pragmatical theories
he looked through a window/
keyhole/used a video camera
the plant was shifted from its place
repetition, somebody
accompanies him, all plants were
moved
somebody assists him
dismiss potential assistant as
well, to blindfold him, …
esoterical theories
he has extrasensory power
no design possible!
13.08.2009
28
Levels of Competence – Developing Hypotheses
I.
without hypotheses:
to achieve an effect, unsystematically approach
II. unsystematical search for hypotheses:
only a few hypotheses, no logical relation between
hypotheses
III. systematical search for hypotheses:
many hypotheses, but no revisions of hypotheses
IV. systematical search for hypotheses and successful revisions of hypotheses
Hammann 2004
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
29
Levels of competence – Handling of Variables
I.
unsystematical handling of variables:
strategies: “change all”, “no plan”, “intuitive”
II. partial systematical handling of variables:
strategies: sometimes systematic: “local changing”: keep variable
constant, with is predicted as responsible for effect
III. systematical handling of variables in known domains
IV. systematical handling of variables in unknown domains
Hammann 2004
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
30
Levels of Competence – Analysis of Data
I.
discussion of data without reference to hypotheses:
only description of effects – no explanation for causes, aim for acquisition of
data is vague
II. illogical analysis of data:
data are related to hypotheses, but illogical conclusions are drawn,
hypotheses are changed or maintained, independent of data
III. widely logical analysis, problems with the appraisal of anomalous data
Anomalous data are often ignored or misinterpreted
IV. adequate analysis of data in reference to hypotheses
Hammann 2004
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
31
Results of Studies – Strategies in Handling Anomalous data
Basically data are not accepted or accounted invalid
-
ignoring anomalous data
rejecting anomalous data
excluding anomalous data
holding anomalous data in abeyance
Basically data are accepted (seldom)
- reinterpreting anomalous data
- peripheral theory change
- theory change
Chinn & Brewer 1993
Dirk Krüger
13.08.2009
Magic moments in scientific inquiry
32
Students´ Conceptions: Controls in Experiments
Controls are part of experiments. Please discribe different controls, that
should be done in experiments!
Controls to enhance the explanatory power of the empirical data
(reliability and validity)
perform repetitions
Nachweisreaktion durchführen
Blindversuch durchführen
Bedingungen konstant halten (Störvariablen beachten)
Parallelversuch durchführen
Kontrollen für Sicherheit und Organisation
Sicherheitsmaßnahmen treffen
Durchführung/Ablauf/Aufbau/Material überprüfen
Kontrollen bezüglich der Objektivität
Protokollieren (Beobachtungen notieren, Veränderungen feststellen,
Vergleichen, Messen)
Kontrollen bezüglich der Nützlichkeit
Effektivität/Aussagekraft/Ergebnis des Experiments
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
33
Students´ Conceptions: Controls in Experiments
Controls are part of experiments. Please discribe different controls, that
should be done in experiments!
Controls to enhance the explanatory power of the empirical data
(reliability and validity)
perform repetitions
– one after another
– simultaneous
– if the experiment malfunctioned
– if somebody casts doubts on the results
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
34
Students´ Conceptions: Controls in Experiments
Controls are part of experiments. Please discribe different controls, that
should be done in experiments!
Controls to enhance the explanatory power of the empirical data
(reliability and validity)
perform repetitions
perform detection reactions
– the integrity of the detection agent
– to achieve the desired effect
– to achieve the effect repeatedly
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
35
Students´ Conceptions: Controls in Experiments
Controls are part of experiments. Please discribe different controls, that
should be done in experiments!
Controls to enhance the explanatory power of the empirical data
(reliability and validity)
perform repetitions
perform detection reactions
perform blind trails
– trail without influencing variable
– trail, where the influencing variable is
varied arbitrary
– trail, where you don´t look at the results
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
36
Students´ Conceptions: Controls in Experiments
Controls are part of experiments. Please discribe different controls, that
should be done in experiments!
Controls to enhance the explanatory power of the empirical data
(reliability and validity)
perform repetitions
perform detection reactions
perform blind trails
keep conditions constant – pay attention to interfering variables
– keep measurement methods constant
– keep influencing variable constant
– keep all approaches constant
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
37
Students´ Conceptions: Controls in Experiments
Controls are part of experiments. Please discribe different controls, that
should be done in experiments!
Controls to enhance the explanatory power of the empirical data
(reliability and validity)
perform repetitions
perform detection reactions
perform blind trails
keep conditions constant
perform replications
– simultanous
– parallel with and without influencing variable
– further studies under changing conditions
(e.g. with other organisms)
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
38
Students´ Conceptions: Controls in Experiments
Controls are part of experiments. Please discribe different controls, that
should be done in experiments!
Controls to enhance the explanatory power of the empirical data
(reliability and validity)
perform repetitions
perform detection reactions
perform blind trails
keep conditions constant
perform replications
Controls for security check and organization
take precautions
check the performance/design/material
Controls concerning the objectivity
record (list observations, determine changes, do comparisons and
measurements)
Controls concerning the usefulness
effectiveness/explanatory power/results
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
39
Thank you for your attention!
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
40
Hautatmung beim Menschen – keiner kennt sich aus!
Bond: Jill died. Her body was total gold-plated,
so that her skin could not breath any more.
Dirk Krüger
Magic moments in scientific inquiry
13.08.2009
41