A judge articulated a nation’s fears after asking a school counsellor a simple percentage. Jon Marcus reports

Attempts to toughen up tests of teachers’ competency have been in the dock this year as critics complain that minorities are being unfairly excluded from the profession.

However, the court cases have revealed another, more alarming, aspect of classroom competency - that nearly half of all teachers would fail even the easier tests.

A Californian courtroom fell silent when an attorney advocating tougher tests asked a counsellor responsible for advising high school students the seemingly simple question: what percentage is 8 of 80?

The educator couldn’t answer.

“I really worry about my kid getting into college if guidance counsellors don’t know percentages,” said US Appeals Court Judge Andrew Kleinfeld, who was hearing the case.

These fears, backed up by evidence that teachers are poorly qualified, have spurred renewed calls for competency tests. They come as burgeoning enrolments and mass retirements are causing dramatic teacher shortages.

The National Commission on Teaching and America’s Future, a group of public officials, business and community leaders and educators, says unenforced standards threaten the goal of providing qualified teachers for all students. The commission recommended that standards boards should be set up in every state, teachers should be licensed and incompetent ones removed.

The commission found that more than 12 per cent of newly-hired teachers have no training, and 15 per cent are employed without having met state standards where they do exist. More than half of all high-school students taking physical science courses and more than a quarter taking maths are being taught by teachers who do not have backgrounds in those fields, the commission said.

And while the average scholastic assessment test score of verbal and maths knowledge for all high school graduates was 505 and 511, respectively, out of 800, those who said they wanted to be teachers scored only 485 on the verbal section and 479 in maths.

Fifteen of the 50 states administer their own competency tests and 20 use a privately-administered test to evaluate their teacher candidates in reading, writing and maths. Critics argue that the test is undemanding. One question asks for the chronological order of World War I, the beginning of the Great Depression, the New Deal and the Korean War.

In Virginia, a third of prospective teachers failed. And while the minimum score varies from state to state, 30 per cent of the people who take it fail on the first try. Barely half of all the would-be teachers who take the test nationally would qualify to teach under the Virginia standards and the state governor wants the test to be toughened.

New Hampshire’s board of education has voted to administer a teacher competency test for the first time this autumn. Previously the state allowed anyone with a college degree to teach in schools. Pennsylvania is toughening up on standards and making its own competency test more stringent after 91 per cent of candidates passed last autumn.

North Carolina took the plunge and imposed higher standards only to lower them again when not enough qualified staff could be found.

The prospering economy is creating another problem by luring the well-qualified into better-paid careers. America’s 3.1 million teachers earn an average of $38,600 (pound;23,500) a year.