  The field of plasma-based particle accelerators has seen tremendous progress
over the past decade and experienced significant growth in the number of
activities. During this process, the involved scientific community has expanded
from traditional university-based research and is now encompassing many large
research laboratories worldwide, such as BNL, CERN, DESY, KEK, LBNL and SLAC.
As a consequence, there is a strong demand for a consolidated effort in
education at the intersection of accelerator, laser and plasma physics. The
CERN Accelerator School on Plasma Wake Acceleration has been organized as a
result of this development. In this paper, we describe the interactive
component of this one-week school, which consisted of three case studies to be
solved in 11 working groups by the participants of the CERN Accelerator School.
