Chemistry Reference
In-Depth Information
not only causes decreased learning efficiency, but also a loss of motivation in the
longer term.
- Criterion of intelligent consolidation:
Terms, methods, and thought patterns, which were built up certain examples,
should be deepened in different variations and contexts in order to make them
flexible for further transfer. Verbalization is therefore essential. Only things that
one can put into one's own words consistently have truly been understood.
Intelligent consolidation also supports “chunking,” i.e., the organization of
independent schemes to a new unit. According to Miller [
30
] working memory
can keep only a fixed number of “chunks of information” that can be processed
at the same time. In particular, grown-ups have only 7
2 simultaneously
operating memory spaces available for processing such “chunks of information.”
For younger students, this number is even smaller because of developmental
psychological reasons. This underlines once more the correlation between the
two previously mentioned criteria (i.e., the necessity of limitation and of consol-
idation). Overloading memory causes a rapid decrease of performance, as
Johnstone [
31
-
33
] and others have convincingly demonstrated with empirical
studies and analyses.
- Criterion of supporting cognitive skills:
Cognitive skills can and should be supported, while respecting the natural limits
set by maturation. The exposure to concrete problems in meaningful and every-
day contexts [
34
-
36
] that require the use of these skills is important. The
learner's repertoire of facts, operations, and strategies has a big impact on the
cognitive performance and should therefore be extended. Consolidation and
application in changing contexts and in the form of different types of exercises
are also essential here. Students should become aware of their own thought
patterns and should be able to abandon concrete external support step by step.
This is necessary for improving their self-concept.
Self-directed autonomy is essential for the cognitive development, according to
Piaget (see Graber and Stork [
37
]) and Aebli [
29
]. The learner has to be
confronted with situations where the cognitive skills, which are to be supported,
are required and experience can be gained. Cognitive structures in students'
brains are differentiated, coordinated, and thereby developed gradually, but
also changed if necessary. Conceptual change is based on the interdependency
of self-consistent cognitive structures and the awareness of
the specific
requirements of the problem at hand.
- Criterion of scientific enculturation:
Students should get to know contents and investigative methods in chemistry
lessons that are representative for chemistry as a science, and that help them at
the same time to understand their own everyday world better, and to develop
their own cognitive skills. They should understand the chemist's language and
argumentation to be led to an attitude that is empirical and rationally oriented.
They should become aware of the value of scientific knowledge, as well as of
its limits (Stork [
38
], Reiners [
39
]).
