Only 27% of schools in regions targeted by today's teachers strikes are closed, according to the Department for Education.
The figure compares to the 60% closures in the same regions during November 2011, the Government said.
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In her message Theresa May praised the "inspirational bravery" and "unbreakable spirit" of Mancunians in the wake of the blast.
ITV News has obtained exclusive footage of the moment armed police raided a house believed to be linked to the Manchester suicide bomber.
The Manchester Evening News set up a JustGiving page asking people to support the families of those affected by the suicide bombing.