  We report the conceptual inventory results of a large-scale assessment
project at a large university. We studied an attempt at introducing materials
and instructional methods informed by physics education research (PER-informed
materials) into a department where most instruction has been traditional and a
significant number of faculty are hesitant, ambivalent or even resistant about
the introduction of such reforms. The changes were made in the laboratories and
recitation sections of the introductory classes, both calculus-based and
algebra-based, introducing PER-informed materials and training the teaching
assistants in student-centered instructional methods. In addition to the
results found in the large lecture classes, we present the results of a small
PER-informed, inquiry-based, laboratory-based class that has been taught as a
special section of the algebra-based course for about 10 years. The assessment
reported in this paper was done using available PER-developed assessment
instruments. The results of other assessment instruments used in the project,
such as free-response pre- and post-tests, are reported in subsequent papers.
The results in this paper inform researchers in PER of the use of PER-informed
materials and instructional methods in a department not unified in the
introduction and implementation of these materials and the results of the
implementation as assessed by PER-based conceptual inventories. We found that
our conceptual inventory scores were lower than many results reported elsewhere
in the literature. However, we did see a statistically significant increase in
the conceptual inventory scores with the implementation of PER-informed
laboratories and the use of student-centered pedagogy in the labs and
recitations. The increase was much greater, if the lecture instructor also used
PER-informed materials.
