A group of the county’s education heads signed off a six-point action plan to persuade the Government to send more money for schools.
The plans also include running school funding events, roundtable discussions and open evenings for Gloucestershire’s six MPs to attend.
There were 22 schools in deficit as of March 31 – one fewer than last year – and 185 in surplus, according to a council document.
One school in Gloucestershire finished the 2018/19 financial year in a deficit of £438,000, according to a Gloucestershire County County document.
Headteachers and governors met at the School’s Forum – a group of the county’s headteachers and governors – to discuss school funding.
Speaking in a meeting on Thursday afternoon, Innsworth Primary School headteacher Lisa Jones said other primary schools are “already looking at deficit budgets for the first time”.
And the money central Government handed the county council last year was overspent by £4million.
The Treasury is preparing to release a spending review for education this Autumn.
According to a council document, the authority said it is “critical we do everything we can to make the case for additional funding.”
Permanent exclusions, a rising number of children with additional needs, and high levels of home education are the reasons for the overspend.
Director of children’s services at the county council, Chris Spencer, said there are now 1,000 children being home educated in Gloucestershire, of which “we do not pay a penny for”.
A county council officer said the £4million overspend is partly from a rise in children needing an education, health and care plan (EHCP).
The EHCPs set out a child’s needs and the support to which they are entitled.
The amount of children with EHCPs is 368 more than what it was this time last year, costing £3.5million.
Mrs Jones expressed concern about the rising number of pupils leaving schools to be educated at home.
She said: “I have had two children leave my school to be home educated.
“They cost more than four times the amount to keep them at my school. The parents lost patience with the EHCP process which is why they chose to home educate.
“When they left, more money to support my mainstream pupils became available. In my case, there were also safeguarding concerns too.”
The county council presented the members a plan to call on the Government for extra money for schools.
The proposal states: “We run a school funding event, in each of the six constituencies in Gloucestershire.
“This purpose of this event would be to bring together headteachers, Members of Parliament and the Local Authority to discuss and tackle school funding issues ensuring there is a common understanding of the issues.
“A school would be identified in each constituency to host an open evening at a time when the local MP can attend.
“All headteachers in the constituency are invited to the school hosting the event.
“The host school chairs a roundtable discussion, so that headteachers are able to share the issues they are experiencing as a result of school funding shortfalls.
“The LA will capture a record of the discussion and will work with headteachers to jointly prepare a short paper with appropriate statistics and a summary of the specific issues.
“The MP is asked to utilise this report to intensify the discussion in Parliament for fairer/better funding for schools, with particular reference to the Autumn Comprehensive Spending Review.”