Black mortarboards got a fashionable upgrade at Yale’s 305th Commencement ceremony on Monday as the graduates added an assortment of personal touches to their traditionally plain caps.

Graduates of the School of Forestry and Environmental Studies wore garlands of plants and flowers atop their graduation robes, while Nursing School students added paper hearts with band-aids to their headgear. Pierson College graduates pasted gold suns from the college’s shield around the tassel on their mortarboards and a few Trumbullians wore bulls’ horns in celebration of their college mascot.

These quirky additions to academic garb added color to the Old Campus event, where only the eight recipients of honorary degrees were identified individually. Yale President Richard Levin ceremonially conferred degrees on 1,281 undergraduates and 2,486 graduate and professional students, but the graduates returned to their schools or residential colleges to receive their individual diplomas.

Levin delivered the Baccalaureate Address to seniors at three separate ceremonies over the weekend, where he returned to the themes of his 2002 address to freshmen: Benjamin Franklin’s “curiosity, independent thinking, and devotion to public service.”

“Attending Yale College was a privilege,” Levin said. “Being a graduate of Yale College is a responsibility — a responsibility to share the fruits of your education with a wider humanity, through leadership and service.”

During Commencement, residential college and graduate school flags accompanied the students as they processed onto Old Campus, and a few student marshals from each residential college and graduate school received symbolic diplomas from Levin at the event. In addition, winners of Yale’s top undergraduate prizes were recognized on stage.

Sunday’s Class Day, featuring an address by CNN news anchor Anderson Cooper ’89, was a less formal affair, with graduating seniors wearing creatively festooned hats decorated with everything from flamingos to fruit platters, following Class Day tradition.

As spectators hurriedly donned blue ponchos and unfurled umbrellas to face the afternoon rain showers, Cooper called on graduating seniors to embrace the ambiguity that they were about to face as college graduates. Cooper, who Senior Class Treasurer Ellen Dabela ’06 said was chosen to speak because of his unconventional rise in the journalism world, told graduates to follow their passions and resist compromising their happiness by taking a safe, predictable career.

“When I was graduating and deciding what to do with my life, I felt paralyzed. I thought I had to figure it out all at once … and I now know it doesn’t work that way,” Cooper said. “Everyone who I know who is successful professionally or personally could’ve never predicted when they graduated from college where they’d actually end up.”

After graduating with a degree in political science — which he said has given him little more than the ability to read a newspaper — Cooper said he had difficulties finding a job. After applying for entry-level positions at various news broadcast agencies and being repeatedly rejected, Cooper said he decided he had to strike out on his own and create opportunities for himself, since no one was willing to give him opportunities. Cooper said he then borrowed a video camera, forged a press pass, and hopped on a plane to Burma to jumpstart his career as an international news correspondent. After spending two years hopping from one war-torn country to another shooting footage and interviewing locals, Cooper said he eventually secured a job at ABC News after showing them his footage. Although Cooper said he valued the time he spent at Yale, he said the experiences he had in the streets of places such as Port-Au-Prince and Sarajevo were more enlightening than anything he had done in his college years.

“I’ve never been asked what my grades were at Yale. … Nobody has ever asked me about my senior thesis, and I’ve never gotten a job because I was on the lightweight crew team,” Cooper said. “All those things were hugely important to me at the time, but right now, in truth they are dim memories for me. … When you graduate the slate is wiped clean.”

Throughout Cooper’s speech, graduating seniors applauded raucously. Starting out with a greeting to “members of class of 2006, friends, faculty, parents, members of the Taliban,” Cooper set the lighthearted and sarcastic tone of his speech with a jab at the Yale Alumni Association.

“You don’t know this about the Yale Alumni Association, but let me just warn you: for the rest of your life, they will hunt you down no matter where you go, no matter what country you live in, they will find you and write you letters and squeeze this for every cent you make,” Cooper said. “If Osama bin Laden was a Yale grad, they would have known what cave he was hiding in.”

Cooper also remarked that standing on stage in front of the 1,281 graduating seniors made him feel old — especially since he was already in his senior year of high school when the class of 2006 first entered the world.

“The only thing about high school I remember is my senior prom … if what I remember is true, it is very possible that some of you are my children, especially you with the blue eyes and freakishly gray hair,” said Cooper, pointing at an audience member. “Let me just say that if that is true, for legal reasons I can’t say that whether you are my children, but I’m bursting with pride today, and I’m sorry for not being around for the last 20 years.”

Many students said they enjoyed Cooper’s speech, which they said had the right proportions of humor and poignancy. But some were worried some of the more risque remarks might have offended older audience members.

“It was hilarious,” Betsy Williams ’06 said. “The Taliban dig may have been a bit much, but it was in a lighthearted spirit. I hope I’m one of those people who can stumble into success.”

Serena Crivellaro ’06 said she had low expectations for the speech, but was pleasantly surprised.

“I heard awful things about Anderson Cooper and I thought he was going to pull all sorts of emotional strings,” Crivellaro said. “But I liked it. I thought it was funny. I hope my parents didn’t mind some of the comments though.”

Following Cooper’s speech and the presentation of teaching prizes for faculty and undergraduate prizes for graduating seniors were announced, there was a moment of remembrance for Rachel Speight ’06, who died while participating in a cross-country bicycle trip for charity organized by Yale students last summer.

Eight honorary degrees were awarded at Commencement to Peter Brown, Zaha Hadid, John Pepper, Moshe Idel, Peter Raven, Edward Albee and Sandra Day O’Connor. O’Connor, the first woman to be appointed to the Supreme Court, retired from the Court last year and received an honorary Doctor of Laws degree from Levin at Monday’s ceremony. At Commencement, Levin praised her groundbreaking career and the moderate opinions she wrote while on the Court.

“Your judicial pragmatism has helped to keep the law a living thing,” Levin said.

O’Connor received a standing ovation from the thousands of students and parents in the audience on Old Campus, and as she accepted her degree, one graduating student shouted, “You go, girl!” to the former justice.

Albee, the author of “Who’s Afraid of Virginia Woolf?” and “The Goat, or Who is Silvia?” has won three Pulitzer Prizes and two Tony Awards for his plays. When giving Albee a Doctorate of Letters, Levin praised his work for capturing the “complexity of modern life.”

John Pepper ’60 served as Yale’s vice president for finance and administration until last year, when he became the chief executive officer of the National Underground Railroad Freedom Center. Before coming to Yale, Pepper worked for 39 years at Procter and Gamble, eventually heading the company.

Hadid was the first woman to receive the Pritzker Architecture Prize, the top award in the field. Brown is a scholar of late antiquity at Princeton and the author of an acclaimed biography of St. Augustine.

Idel is a scholar of Jewish mysticism — Kabbaleh — at the Hebrew University of Jerusalem. Raven heads the Missouri Botanical Garden, the oldest public garden in the United States and the site of a research center for tropical rain forests.