Although there have been sightings reported, the girls have never been found. Boko Haram leader Abubakar Shekau has said the girls have been converted to Islam and married off.
The abduction caused global outrage.
It sparked a huge Twitter campaign, #BringBackOurGirls, and countries including the US and China vowed to help find them.
This week marches were taking place in Nigeria and various cities worldwide, with protesters, supported by United Nations Secretary-general Ban Ki-moon, pledging not to forget the girls.
Nigeria's incoming President Muhammadu Buhari is talking tough, too, vowing to ''crush'' the insurgents.
There is certainly hope he is willing and able to do more than his predecessor Goodluck Jonathan, who has been widely criticised for overall failure to act in the face of the militants, who recently pledged their allegiance to the self-proclaimed Islamic State, whose modus operandi in Iraq and Syria has become the new and horrific face of terrorism.
Mr Buhari has previously proven a tough leader, with a crackdown on corruption, which he campaigned on again this time.
He also campaigned on security issues and he carries many people's hopes and expectations on his shoulders.
But it remains to be seen what effect he can have on Boko Haram, and if he can in fact ''bring back the girls'' to their families.
The dangers in attempting to do so cannot be underestimated.
The appalling reality is they are only the tip of the iceberg.
Amnesty International believes (based on testimonies from witnesses and escapees) at least 2000 girls have been kidnapped by the militants, and turned into cooks, sex slaves, and fighters for the Boko Haram.
Those who refuse to convert or fight are killed. Many thousands of others have also been killed in the six-year insurgency, and Unicef says 800,000 children alone have been forced to flee the fighting.
There is international sympathy for the plight of those caught up in the fighting.
As IS has shown in Iraq and Syria, international support may be required - and sought.
But it is to be hoped, in the first instance, Nigeria can make a real effort to tackle the terrorism in its own backyard itself.
While it is reassuring to see the girls still making headlines, there are a great many people out of the spotlight whose fates are uncertain.
It is important to note the regime's own human rights abuses, too: the abuses and atrocities carried out by the police and security forces, and the hundreds of people languishing on death row awaiting the death penalty, for example.
Mr Buhari has more to do to protect Nigerian children and citizens than simply defeating Boko Haram.
And another thing
United States President Barack Obama's intention to remove Cuba from the US list of state sponsors of terrorism further speeds the thaw between the two former Cold War enemies.
Mr Obama and Cuban President Raul Castro met last weekend, the first such meeting between US and Cuban leaders in nearly 60 years.
The decision to restore ties has not been without criticism from some quarters however, mainly Republican lawmakers opposed to reconciling with the communist-run island.
And there is still a long way to go, with major differences in opinion about democracy and human rights.
Nevertheless, the thaw in relations - the result of 18 months of secret talks facilitated by the Vatican and Canada - has been welcomed by many.
United Nations Secretary-general Ban Ki-moon has praised Mr Obama for his courage and vision in renewing ties with Cuba.
The two countries certainly appear to be firmly on the path to restoring full diplomatic relations, which can only be positive for the thousands of exiled Cubans in the US, and elsewhere, for world stability.
