And, a year on, there's a growing recognition that the girls may never be brought back.
"We do not know if the Chibok girls can be rescued. Their whereabouts remain unknown," Nigeria's president-elect, Muhammadu Buhari, said in a statement on Tuesday. "As much as I wish to, I cannot promise that we can find them."
(The AP's Lagos correspondent tweeted this image of some of the missing girls.)
Buhari's frankness on the matter was an attempt to distinguish himself from the man he defeated in a recent election, President Goodluck Jonathan, whose administration was widely accused of bungling the response a year ago. Jonathan, to this day, says domestic political rivalries hampered his efforts. Some observers suggested that, at least initially, he seemed more interested in quieting criticism of his government than carrying out a meaningful rescue operation.
"We hear the anguish of our citizens and intend to respond accordingly," Buhari said Tuesday. "This new approach must also begin with honesty."
Activists turned the girls' abduction into a larger movement about the apathy and corruption of Nigeria's ruling elites. If it was a societal wake-up call, it doesn't seem to have changed much on the ground. The slogans bandied about at marches this week shifted forlornly from #BringBackOurGirls to #NeverToBeForgotten.
The girls were abducted by a deadly militant organization that is opposed to their education. "They told us we shouldn’t be in school. That education, 'book,' is bad, 'haram,' and that we should come with them," Saratu, a 19-year-old Chibok girl who fled the militants and was spared the fate of her friends, said in an interview with Voice of America.
Malala Yousafzai, the Pakistani Nobel laureate and teenage education campaigner, issued a statement on Tuesday offering "solidarity, love and hope" to the kidnapped schoolgirls of Chibok. She referred to her own suffering at the hands of Islamist militants:
Like you, I was a target of militants who did not want girls to go to school. Gunmen shot me and two of my friends on a school bus. All three of us survived and are back in school. Now we speak out on behalf of all girls about the right to get a proper education. Our campaign will continue until you and all girls and boys around the world are able to access a free, safe and quality secondary education.
To be sure, the havoc wreaked by Boko Haram, as my colleague Kevin Sieff reports, extends far beyond these schoolgirls. A UNICEF study published this week found that nearly a million Nigerian children have been forced from their homes because of the militants' onslaught.
"Children have become deliberate targets, often subjected to extreme violence – from sexual abuse and forced marriage to kidnappings and brutal killings," says the report, titled "Missing Childhoods."
Boko Haram militants have killed more than 1,000 civilians this year alone, according to Human Rights Watch. Roughly a million Nigerians have been displaced since the Islamist insurgency flared in 2009. Some critics say the heavy-handed response by Nigeria's military has not made things better.
"People are afraid of the military and security forces as much as they are afraid of the insurgents," one civil society activist told PBS's Frontline last fall. "Innocent people bear the brunt of this insurgency and counterinsurgency."