Normally, each student develops their own paper, independently
of the other students. But one option is to work on a JOINT
author paper.

Some guidelines regarding Joint Author papers:

(1) Each of you will need to SUBSTANTIALLY contribute to the paper,
at the same level as if you were each developing your own paper.
This implies a larger paper to make sure that each of you
makes significant contributions to the joint paper.  The analysis
part of the paper should be proportionally larger (at least 12
pages PER joint author).  This means that you may need additional
examples, additional figures, and/or deeper explanations for the
required analyses.  The overhead portions of the paper (everything
but the required analyses) don't need to be larger for a joint
author paper.  

(2) In the paper's abstract, be sure to have a brief biography
for EACH joint author.

(3) You need to carefully delineate which of you contributed to
specific sections.  How you do this is up to you, but I suggest that
one easy way of assuring this is to divide up the writing of the
Introduction, System Description, Conclusion, etc. and then each
contribute something individually for each of the required analyses
(see Research Paper checklist).  Perhaps you want to offer a paragraph
from each of you, offering different perspectives, or perhaps one
of you contributes the figure and the other person contributes
the text.  Then BE SURE TO CLEARLY INDICATE "WHO CONTRIBUTED WHAT"
in each section!  The point is to demonstrate that you contributed
equally to the development of the paper in terms of level of
effort-- that one person didn't do most of the work.