Moreover, the reading material that was available in the
control and experimental conditions was matched. Students in
the experimental conditions had available as reading material
their lab notebook that they were completing themselves as
they were progressing with the conduction of the experiments
of the curriculum material. What was included in the lab
notebook was determined by the curriculum material through
specific questions and activities (e.g., construction, interpre-
tation and discussion of a graph). Students in the control
condition were given at the beginning of each section
a ‘‘textbook’’ (a compilation of notes) that included
a description of the experiments to be shown in class and the
same accompanying questions and activities as the ones given
to the students in the experimental conditions. Students in the
control condition were responsible to answer the questions and
do the activities themselves during class. They were also
allowed and encouraged to discuss their responses to these
questions and activities with their peers (as students in the
experimental condition did) before having whole class
discussions with the instructor. In the case where students
needed data to do an activity, such as constructing a graph,
ready-made data was provided to them through their ‘‘text-
book’’ or by the instructor.