Schools face "terrifying" cuts as part of a government rescue plan following overspending of a council's SEND budget, a teachers' union has warned.
Bournemouth, Christchurch and Poole (BCP) Council has been asked to join the government's Safety Valve scheme as its deficit is predicted to be £63.4m.
More than 2,000 people have signed a petition opposing school spending cuts.
The government said Safety Valve was about using "available funding in the best way".
The national programme is designed to help local authorities tackle overspending on special educational needs and disabilities (SEND) services.
It offers investment from Department for Education (DfE) but local authorities must agree to balance their education budget.
BCP Council is forecasting a £63.4m designated schools grant (DSG) budget deficit by 31 March as a result of overspending its SEND budget.
A plan to balance BCP Council's books in five years has been rejected by head teachers and the council, but they have offered to do it in 15 years.
Head teachers rejected plans to cut 0.5% from their budgets to fund SEND support at the authority's schools forum on Monday.
