Hi Susan,
The parade routes will be shown on the Guide Map you pick up as you enter the parks. To give you a general idea, at the Magic Kingdom, it can start or end in Town Square & goes down Main Street, around the hub in front of Cinderella Castle, then travels toward Liberty Square, takes a left & ends near Splash Mountain in Frontierland.
At Animal Kingdom, it begins & ends near the entrance of Kilimanjaro Safaris & makes a loop that goes through Discovery Island & past Flights of Wonder.
At Hollywood Studios it travels down Hollywood Blvd, takes a left at the Sorcerer's Hat & ends near Star Tours.
I'm not sure which parks your are planning to visit so I glanced at the online calendars for all 4 theme parks. Its looks like they have some but not all of the usual listings up but I think they will likely add some to the schedules as May gets closer. You can check the parade & fireworks schedules online by clicking on the following links:
Magic Kingdom
Disney's Hollywood Studios
Disney's Animal Kingdom
Epcot
From there, select May 2011 from the drop down list next to the
View Month tab. That will take you to that month's calendar which will list park hours & Extra Magic Hours. Click on a specific day for parade & fireworks schedules. Be sure you pick up a Times Guide as you enter the parks to confirm as schedules are always subject to change without notice.
Let me know if you'd like me to check any specific dates for any of the parks. Wishing you many magical memories :-) Allison