New York City’s Cooper Union is one of the nation’s great private universities. Founded in 1859, it was from the start an experiment in radical accessibility — open to women and people of color and students of any religion, free to the working class. And since 1902 it has accepted students on a need-blind basis, charging none of them a penny in tuition. Today the college is among the most selective in the country, and though more than two thirds of its students come from public high schools, the average graduate leaves Cooper Union with just $10,000 in debt.

But that may be about to change.

Last year the college announced that it was considering charging tuition for the first time since 1902, citing the economic downturn, poor investments, and a series of expensive capital projects. This year Cooper Union began charging tuition in its graduate programs, and though undergraduate enrollees for the fall of 2013 have been promised a tuition-free education, no similar pledge has been made for the following year.

Students have been mobilizing against the tuition plan since it was first proposed, and today marks their biggest day of action and outreach yet. Starting at noon, the activists of Free Cooper Union will be holding a day of free classes and demonstrations at the campus’s Peter Cooper Park, followed by a three-hour Summit on Debt and Education at the college’s Great Hall at six pm.

Afternoon Update | Students have barricaded themselves inside the top floor of the college’s Foundation Building, demanding a return of free tuition, governance reforms, and the resignation of the college president. Ongoing coverage here.