SCOTTISH pupils sat a computing science paper that was "riddled with errors" and even included a question that could not be answered, according to teachers.

Computing science specialists have launched an outspoken attack on this year's National 5 exam highlighting problems with 19 out of the 21 questions.

Teachers described the paper as one of the worst ever set and called for the Scottish Qualifications Authority (SQA) to hold an immediate inquiry.

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Typographical errors included a question that read: "Give one reason of using this type of selection" while in another question the weight of a tablet computer was given as 65kg.

Critics also highlighted confusing questions, questions with multiple possible answers and some where knowledge would have been required from outside the course such as the legislation around cloning of phones.

However, despite the widespread criticism the SQA said there was nothing wrong with the paper and insisted it met all its requirements.

HeraldScotland:

The controversy comes at a difficult time for computing science in schools with falling teacher numbers and concern the importance of the subject to the future economy is being ignored.

The SQA has also been mired in controversy over problems with the setting of other exams with a number of pupil petitions highlighting issues with Higher mathematics and Higher English.

The concerns about the National 5 computing science paper came to light in a number of internet forums used by specialist teachers of the subject.

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One teacher from a high profile Edinburgh private school described the paper as "the most error-strewn and, in places, incomprehensible examination I’ve seen in my career".

He said: "It contains typos, incorrect code and other errors which make questions unanswerable. It is strewn with grammatical errors, it requires knowledge which is not in the course and some questions are so poorly designed and worded that even the most able and best-prepared of candidates could well be defeated by them.

"There has clearly been insufficient quality assurance, as even the most cursory glance by an experienced computing science teacher would have picked up many of these errors. At best, the paper reads like a first draft; could the explanation be as simple as an incorrect version being published?

HeraldScotland:

"At a time when computing science faces an existential threat in some parts of the country, colleagues and pupils need to be better served than this."

Another teacher stated: "I am very disappointed with the quality of this paper overall and personally, I think this paper is a disgrace and am really wondering if it actually went out to any checkers."

A third said: "In the past we’ve had questions repeated multiple times in papers and answers to one question given away in the blurb of others.

"This paper has both of those, but in addition has questions that cannot be answered, sloppy program code that relates poorly to the questions that reference it and much much more.

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"Surely this is has to be the final straw or will the thin-skinned SQA apparatchiks deflect and defend this on the basis that it doesn’t matter as it’ll all be balanced out by adjusting the pass marks and grade boundaries?"

Other comments stated: "I am more disappointed that a massive organisation such as the SQA is able to send out a paper with so many mistakes in it especially when they have been slated over the years for issuing computing science teachers with assessments and documentation with so many mistakes in it."

HeraldScotland:

An SQA spokesman said: "The National 5 computing science exam paper met our course and assessment specifications and allowed candidates to demonstrate their knowledge and understanding. The anecdotal feedback we have received from teachers and candidates has been positive."

In 2014 it was revealed that the number of computing science teachers in Scotland has dropped sharply, sparking fears for the future of the subject.

New figures show teacher numbers in the subject have fallen by 109 in the past two years - a drop of 14 per cent. One in eight secondary schools in Scotland does not have a computing science specialist at all.