Sample Term Papers

I was forwarded a job announcement from the largest national Hispanic non-profit civil rights and advocacy organization in the U.S. The application procedures say the following: “mail, fax, or email cover letter, resume, and writing sample (2 pp.) to…”
What does “pp.” mean, and what is a suitable writing sample to send them? I am a student that is still in college, and so most of my writing samples are term papers, etc. I have written for a local newspaper – a piece that highlighted the service of two local soldiers (they were going to be recognized by the community/dignitaries at a local event). So, what should I send and how many samples? What samples should I stay away from sending? Thanks!