  In this paper we explore the theory of communities of practice in the context
of a physics college course and in particular the classroom environment of an
advanced laboratory. We introduce the idea of elements of a classroom community
being able to provide students with the opportunity to have an accelerated
trajectory towards being a more central participant of the community of
practice of physicists. This opportunity is a result of structural features of
the course and a primary instructional choice which result in the development
of a learning community with several elements that encourage students to engage
in more authentic practices of a physicist. A jump in accountable disciplinary
knowledge is also explored as a motivation for enculturation into the community
of practice of physicists. In the advanced laboratory what students are being
assessed on as counting as physics is significantly different and so they need
to assimilate in order to succeed.
