A head teacher said she might be forced to cut staff to pay for the school's rising energy bills.
Debbie Whiting, head of North Denes Primary School in Great Yarmouth, said she was facing "an awful lot of pressure" over finances.
She said she faced finding £21,500 to pay for teachers' pay rises, as well as money to cover a forthcoming 400% hike in its electricity bill.
The government said schools' budgets would rise by £7bn by 2024-5.
The Norfolk school is in one of the country's most deprived areas. It provides a breakfast club, food and uniform bank, and cookery classes for people on a budget.
