Just FYI - NPC groups (
http://www.npcwomen.org/) no longer refer to it as pledging. We call it a New Member period. Every group might have a different formal name but no one calls it pledging.
The period is designed to get the NM acclimated to the organization and how it relates to college life and beyond. Remember also that although you are interested in developing a NM program, you want to have relevant programming for the entire chapter.
Components can include: History (the history of the organization, chapter history, and/or Greek Life history going back to Phi Beta Kappa), Philanthropy (fundraising or hands on activities (like tutoring elementary school kids) for a national or local cause), Academics (get someone from the school’s tutoring center to come in and council. Topics can range from study tips to how to use the library system.
I only add the last bit because some schools have 3 or more libraries and it wouldn’t do much good to do an English lit paper in the engineering library.), Cultural interests (invite someone from the local theatre or symphony to come and speak or better yet go to those places as a group, have a poetry night or an anthropology professor to speak about her latest work), Fraternal Spirit (retreats, learning songs, get ice cream), Life Skills (have someone from the career counseling center to come in and discuss how to write a resume, how to prepare for an interview, remind them about upcoming job fairs), Public Relations (co-sponsor an event with another club or even a department, put announcements in the paper congratulating members on recent accomplishments) and Risk Management (address mental and physical issues, show how to avoid potentially hazardous situations and conflict resolution).
These are just a few ideas to get you going. The main thing for you all to do is to design a program for your needs. Most NPC groups have NM periods from 6-8 weeks in length because of schools breaks and such. Some groups use a full semester because they require end of semester gpas for initiation.
Good luck!