Touring Shakespeare companies that help 14-year-olds to prepare for key stage 3 Sats are facing a fight for survival now that the tests have been scrapped.
One of the largest firms said it could lose 80 per cent of its business as schools cancel bookings because work on the Bard will not be tested next year.
Companies usually run Shakespeare workshops with Year 9 pupils in the four-month run-up to the Sats in May.
The firms' anxiety follows the announcement to scrap the tests made earlier this month by Ed Balls, the Schools Secretary.
Nic Brownlie, who runs Mopa Theatre Company in Hertfordshire, said 12 schools had cancelled bookings in the 10 days since the decision.
He said not a single school had contacted his firm to make a booking for the coming spring season since the Sats announcement. It would normally take 20-30 bookings at this time of year, he said.
Mopa usually runs four touring companies, each with four actors, taking productions to about 240 schools in spring. But it said there would now be just one touring group. It stands to lose more than Pounds 150,000, 80 per cent of its business.
Mr Brownlie said the decision had come out of the blue and that schools had been both shocked and delighted.
"They were never the best set of tests," he said. "But the complete unexpectedness of it has really knocked us back. My frustration is with the Government, which appears to have taken this decision without considering the impact on people such as ourselves.
"We have had some schools ring up and say, 'You are great - you are about so much more than Sats'. But one or two have said senior management want to claw back the money for other things.
"I thought what we were doing was developing young people's appreciation of Shakespeare. What it was related to was Sats preparation. Poor old Shakespeare would be turning in his grave if he knew that he was only valued because of the Sats tests."
Natasha Crosher, of Shakespeare Works, a small firm which uses only four actors, said five of the 38 schools that had booked a production for its spring season had pulled out. Ten had rung to offer their support.
She said some schools could fund enrichment work only where it was directly linked to exams, and that some would now re-allocate it for GCSE work with "borderline" pupils, unrelated to Shakespeare.
Ms Crosher said: "Some senior managers are saying, 'We need that money for CD intervention work at KS4.' Or they are saying, 'We charge the parents for what you do. If it's about passing an examination, parents will pay, and because it's no longer about passing an exam, we don't think parents will pay'."
London's Globe Theatre has also run workshops, but does not think it will face fewer bookings because it can easily broaden their scope.
Katharine Grice, spokeswoman for the theatre's education projects, said she knew some teachers still wanted to focus on set scenes because their schools would continue setting KS3 tests internally.
"We are delighted if it means more schools want to look more at whole plays as that is much more in tune with the way we think Shakespeare should be taught," she said.