The evening march is not the only action happening on March 20th. A number of student groups are meeting today (Sunday) at UIC to talk about walking out,organzing feeder marches and other actions earlier in the day.

IMO, any discussion of direct action against local corporate war profiteers, recruiting stations ect. before the evening march will probably occur offline. If you want to do something - nothing prevents you from organizing an affinity group, making an action plan and lining up the necessary logistical support.

The key here is initiative.