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The effect of different task formulations on
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3 Fishing an ice cube: The test persons have to find a way (to reach a solution) to get an ice cube out of water() without getting whet fingers.
Using Type-II tasks the test persons got the following question for the first experiment: „Is it able for you to put the egg into the bottle without damaging it?” Different kinds of materials were offered on a table, for example: vaseline, a funnel, an egg-pricker, a toy-hammer and matches.
To find a solution for this experimental problem the test person has to use prior knowledge and its creativity. Using a type-I task the instruction was very clearly defined and the test persons just got the materials they need to do the experiment.
1.” Light a match and put it into the glass bottle.”
2.” Quickly put the egg with the pointed side down on the opening of the bottle.”
In order to examine whether or not their experiences led to profound learning processes, they were given transfer tasks. For example:
“You want to save your summer clothing during the winter. Therefore you take a plastic sack and put your summer clothing in it. Afterwards take a vacuum cleaner to suck the air out of it. What will happen?”
1. The clothing is suck into one corner of the plastic-bag so you got space for more clothing.
2. The sac becomes very small and covers the clothing.
3. The clothing gets dust-free, but nothing happens to the bag.
To establish the effect of using different types of task formulations a combination of observation and transfer task was used. In this examination the following observation-sheet was used. This observation-sheet is especially suitable to observe learning habits in science centers, because it can be used independent of age and experience of the test person.
Categories to judge work and learning habits A Observing others experimental work.
CATEGORY I:
“attention”
B Looking at the experiment.
C Active experimental work.
D Showing positive reactions.
CATEGORY II:
“perception/awareness”
F Asking questions about the experiment.
G Repeating parts of the experiment.
H Going into the experiment. CATEGORY III:
“understanding”
I Testing variables.
49 K Asking for more information.
L Using experience.
M Leaving experiment after a short time.
CATEGORY IV:
“negative reactions”
N Breaking off the experiment at an early stage.
Tab. Tab. Tab. Tab. 1:1:1:1: Categories to judge work and learning habits
The categories I to III show increasing participation in the experiment and increasing depth of learning. Category IV records negative reactions of the test persons.
b) Group of 8th grade students in school
In a further survey, two groups of students from 8th grade were provided with the two types of differently formulated tasks. The beginning of the lessons was the same in both classes. First they were shown several pictures of salt mines and () a chunk of a salt-sand-crystal. The exercise was to split up a salt-sand-mixture.() One group had a task I formulation – which was very clearly defined – the other group a type II formulation. Both groups were provided with the needed equipment.
Type I:
Fill up the salt-sand-mixture with as much water as needed to dissolve all the salt. Pour the mixture through a tea strainer ( first ) and afterwards through a funnel with filter paper in it. Catch the filtrate in a glass. Heat the filtrate as long as the whole water is boiled away and you receive back the salt.
Type II:
Develop a plan to solve the following problem:
You get a salt-sand-mixture. Separate the mixture in its parts.
While the pupils were doing the experiment their (experimental) behaviour was recorded on video.
The following hypotheses were formulated and verified in this investigation:
• Less detailed types of tasks stimulate examinees to work both creatively and independently .
• Active and very bright examinees show a more positive attitude to work when confronted with less determined test conditions.
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To look into the work and learning habits the observed conductions have to be coded. Therefore a category-system called „pupil working habit“ was developed for this examination. This system can be divided into 8 action-categories, which can be observed objectively. Time phases of each pupil from both classes are coded with the observed action-categories.
„pupils working habit“
Category Activities
1 Reading the task.
2 Talking about the experiment.
3 Doing the experiment.
4 Looking to the place of happening.
5 Writing down observations.
6 Asking the teacher or other group / looking at other groups experiment.
7 Activities which don't belong to the lesson.
8 Other activities.
Tab 2: Category system: “pupils working habit”
The following illustration shows the software program „videograph“ which has been developed by Rolf Rimmele at the IPN in Kiel. This program was used for the coding.
Fig 1: User interface: “videograph”
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Ice coup Blowing up a bag Egg in a bottle
There are three windows at the user interface:
Top left you can see the video file Top right action-categories Down time strips
In this illustration you can see the category-system for the tree pupils with 8 action-categories.
Each time strip for each pupil can be coded by a mouse click with the observed action-category.
The coded process data can be exported to other programmes like SPSS or EXEL, to create a set of statistics.