Piazza has announced that it has secured $6 million in Series A funding, led by Bessemer Venture Partners. The social learning network for students and instructors will use the money to expand its interactions and outreach efforts.

“Bessemer invested because we believe that Piazza can lead a communications revolution in higher education,” said Ethan Kurzweil, Vice President at Bessemer Venture Partners who recently joined Piazza’s board of directors. “Across every sector, the world is witnessing seismic shifts away from clunky, centrally-mandated software packages towards tools designed from the ground up to be social and collaborative. That wave is breaking in education, and Piazza is best positioned because of its ability to create positive engagement among users. I wish I’d been able to use Piazza when I was in college myself.”

“In BVP we found a partner that shares our vision for a social learning network that transforms education,” said Pooja Sankar, Founder and CEO of Piazza. “This year we will expand our platform to support more open-ended interactions among students and encourage new forms of social learning, stretching beyond the traditional classroom. As we execute on our mission, we will draw on BVP’s wealth of experience in helping companies to scale from initial customer successes into lasting businesses.”

Piazza, which emerged from private beta in January and how has over 100,000 students at hundreds of schools worldwide, including 109 of the top 250 colleges in the U.S. Designed to be an environment that students can ask questions under the guidance of their instructors, students who sign on to Piazza stay logged in for an average of four hours a day.

During the Fall 2011 term, 96 percent of the questions posted on Piazza were answered, with 45 percent receiving an answer from a student and 67 percent addressed by instructors. Most active class on Piazza was a computer science class at Berkeley, where students recorded over 19,000 contributions during the course of the semester; one student in this class answered 463 of his peers’ questions while 74 percent of the students contributed, which is 7.5 times the industry norm for online communities.

“I demand deep engagement from my students in the classroom,” said Srinivasan Keshav, Professor and Canada Research Chair at the University of Waterloo. “With Piazza, for the first time I can expect a level of engagement outside of class that enables me to challenge my students with harder problems. I know they will work through them and learn together using Piazza then come to class knowing what they need to learn. That’s not just a better way to get questions answered, it’s a more effective style of teaching and learning.”

“People are making a big deal out of Berkeley choosing gmail as its email solution, but nobody I know uses email unless we’re forced to,” said Tianbo Xu, a student at UC Berkeley and the president of the school’s IEEE student branch. “We’ve grown up with a more social communication style, but at the same time a lot of students are reluctant to participate in class forums because they don’t want to seem too smart or too dumb. Piazza has figured out how to create a vibrant social network centered on your class without demanding that you disclose everything. Once you’ve used it, it’s hard to imagine not using it.”