  Due to its amazing three-dimensional effects, holography is a very
motivating, yet very demanding subject for physics classes at the upper level
in school. For this reason an instruction unit on holography that supplement
holographic experiments with computer-supported work sessions and a simulation
program was developed. The effects of the lessons on holography were determined
by a pre-post-test design. In addition to videotaping the lessons, knowledge
and motivational tests as well as student interviews, students were asked to
prepare concept maps, which were used to track processes of model construction.
The way this knowledge was applied largely depends on the students'
understanding of models. In particular it was shown that the participating
students' demonstrated capacity for distinguishing between the different models
of light is of great importance. Only students with a developed capacity for
distinguishing between models are able to reason in an problem-oriented manner.
They recognize the limits of models and are not only able to specifically
designate changes from models and levels of models, but also to apply these in
a physically correct manner.
