The massacre is the worst in Germany's post-war history
The Gutenberg school in Erfurt, scene of the bloodbath, did not open its doors on Monday morning.
Students instead gathered in the city hall for a minute's silence at 11:05 am (9:05 GMT), the moment when police were first alerted to the events unfolding at the school on Friday morning.
They were due later to join their peers from other schools in the city for a service at Erfurt cathedral in honour of the victims.
Meanwhile in Berlin, politicians began trading insults and apportioning blame for Friday's massacre, the worst incident of its kind in Germany since the end of World War II.
Censorship debate
Correspondents say the issue of law and order now looks set to dominate the campaign for September's general election, when Gerhard Schroeder's ruling Social Democrat Party (SDP) faces a strong challenge from the conservative Christian Democratic Union (CDU), and their candidate for chancellor, Edmund Stoiber.
Mr Stoiber and CDU leader Angela Merkel have arrived in Erfurt to take part in the memorial ceremonies and have postponed the scheduled publication of their election manifesto - widely interpreted as a sign that the document is being redrafted to take into account Friday's events.
They followed on the heels of Mr Schroeder and his foreign minister Joschka Fischer, who had attended a church service in the city on Saturday.
The availability of violent videos such as those found at the home of 19-year-old killer Robert Steinhaeuser, and Germany's gun laws have meanwhile dominated the political debate.
Mr Stoiber has called for an immediate ban on video and computer games which "glamorise violence", while one of his close allies, Bavarian interior minister Guenther Beckstein, accused Chancellor Schroeder's government of "a scandalous level of inactivity" by its failure to impose such measures when the idea was last suggested two years ago.
Interior Minister Otto Schily declared Mr Beckstein was "shamelessly" seeking political mileage from the issue, but politicians from the country's two main parties were nonetheless agreed that restrictions needed to be placed on the sale of such items to young people.
Chancellor Schroeder has also invited the heads of Germany's top national broadcasters to talks on curbing violence in the media, according to a government spokesman.
Sections of the liberal German media however doubted that censorship could have prevented Friday's massacre, or that blaming violent images in the media for the behaviour of a disturbed individual would prove a productive means of dealing with the issue.
Gun laws
Politicians are also due to re-examine Germany's gun laws in the light of Friday's events.
Robert Steinhaeuser, a member of a gun club, had acquired both the weapons and ammunition he used in Friday's massacre legally.
He had licenses for both the Austrian-made Glock pistol, which carries up to 18 rounds, and for the pump-action shot-gun he had strapped to his back when he marched through the school on the rampage, killing former teachers, two pupils and a policeman who was called to the scene.
Mr Schily told German television that the government would examine thoroughly whether the age at which one can legally acquire a weapon should be lifted from 18 to 21, at which age, he argued, people were more "stable".
Gun clubs have however been quick to point out that stricter controls on legal weapons will make few inroads into stopping crime, as most shootings involve illegal arms.
Mr Schily acknowledged that such weapons were the "big problem". There are millions of illegal firearms in the country - the majority of which have been smuggled in from eastern Europe.