UNIONS have called on Kirklees Council to halt Public Private Partnerships and launch an independent investigation.
The call has been made after the council's Cabinet axed support services group Jarvis from its special schools building programme.
The £25m contract was to build four schools with a 25-year agreement for maintenance, which could have totalled another £40m.
The council ended the deal after being unable to reach financial guarantees over the scheme because of troubles plaguing Jarvis.
Work on a special school at Newsome was halted in the summer when building contractors Totty walked off the site because of fears over Jarvis' future.
Jarvis is experiencing financial difficulties. Its chief executive left the company this week and it lost a £177m schools contract in Fife in August.
But Government policy obliges councils to enter into Public Private Partnerships to build new developments.
Mike Forster, Unison's chief steward for education, said in a joint unions statement that they had been warning since 2001 that Jarvis was in trouble.
"Private companies cannot be trusted to run our schools," he said.
"Staff, students and parents have been left in disarray.
"Public services should be the property of the public. End the PPP farce now."
Previous maintenance work undertaken by Jarvis on 20 Kirklees schools had been a disaster, he said.
Kirklees Council has appointed the QED consortium, headed by the Wates Group, to take over the special schools contract. Executives are studying the details.