Freedom of religion in Iceland is guaranteed by the 64th article of the Constitution of Iceland. However at the same time the 62nd article states that the Evangelical Lutheran Church shall be the national church (þjóðkirkja) and the national curriculum places emphasis on Christian studies.
A religion tax is collected by the Þjóðkirkja. Those that belong to other religious groups do not pay that tax, but those who are registered as non-religious (not belonging to any religious group) do pay the tax which used to be earmarked for the University of Iceland but now goes into the tax budget.
The national curriculum requires special classes on Christian studies from first grade, other religions are vaguely mentioned in social studies.
At birth any child is automatically registered to the same religious group as the mother, irrespective of the father's wishes or his group.