Schools in Peterborough should not shut except in extreme circumstances, said the city council.
Teachers are taking part in a national strike on Tuesday (July 5) as they seek further school funding and talks on contracts and workloads.
Sir Harry Smith Community College in Whittlesey has already said it will shut during the day of action, but currently no Peterborough schools are expected to follow suit.
A Peterborough City Council spokeswoman said: “We have written to all schools in Peterborough asking how they will be affected on the day of the strike.
“All schools have been advised that they should do everything in their power to remain open.
“Headteachers may decide to close or partially close their school on the day of the strike, however this decision is out of our hands.
“That said, we are reminding headteachers that closing a school should only be necessary in extreme cases.
“The Department for Education advises that in the event of strike action at a school, headteachers are expected to take all reasonable steps to keep the school open for as many pupils as possible.
“Wherever possible, governing bodies should make all reasonable efforts to ensure children can still receive their education, taking into account health and safety requirements.”