More than two hundred schools across the Anglia region were reported to be closed or partially closed by strike action early on Thursday.
Some teachers are joining other public sectors workers like firefighters, civil servants and bin collectors on a one-day strike over pay.
By 6.30am, more than 80 school in Norfolk were affected by the industrial action with 40 more in both Cambridgeshire and Suffolk. There were also school closures reported in Luton and Northamptonshire.
The region's bracing itself for the largest Public Sector strikes since 2011.
How the public sector strikes could affect you
Public sector workers, including teachers and other school staff, are expected to strike on Thursday 10 July forcing some schools to shut.