University of Southern California [corrected per comment below] students developed the online game for the Annenburg Center for Communications to teach about the challenges (and partisanness) of redistricting. Along the way players learn that to keep their candidates elected they may need to examine ethical issues. The game is Flash-based.
From the site:
The Redistricting Game is designed to educate, engage, and empower citizens around the issue of political redistricting. Currently, the political system in most states allows the state legislators themselves to draw the lines. This system is subject to a wide range of abuses and manipulations that encourage incumbents to draw districts which protect their seats rather than risk an open contest.
- News 10