More than 200 schools are closed in Derbyshire due to the national strike over public sector pensions.
So far 81 schools in Derby are closed, along with more than 120 county council-run schools.
Joint union marches are taking place in both Chesterfield and Derby to protest at government plans to reform pensions.
The 24-hour walkout is expected to cause significant disruption to services across Derbyshire.
The government said with people living longer, the cost of public sector pensions is rising and reforms are desperately needed.
It added that it was trying to make the pension situation fairer for taxpayers and the plans represented a "good offer".
In Chesterfield a rally is being held at Club Chesterfield, on Chester Street, following a march from Rykneld Square which got underway at 11:00am.
Derbyshire County Council said its services were likely to be affected but it "would continue to provide services to the most vulnerable people".