Failure to show essential working is costing Higher maths candidates marks, examiners have warned.
"It is clear, from workings given, that some candidates are annotating diagrams on the question paper and not copying these to the answer booklet, and so essential working is missing from their solutions," says this year's external assessment report.
Teachers also need to give their pupils more practise at "proving" the formula in optimisation questions, while in integration questions candidates should ensure they use the correct notation.
Pupils aiming for an A or B pass at Higher should be exposed more frequently to non-routine problems.
Section A of Paper 1 - objective-type questions - do not incur penalties for wrong answers, so candidates should not leave any of them blank.
At Intermediate 2 level, some candidates had problems with negative numbers, eg, in calculating the gradient of a straight line or in adding or subtracting the equations when dealing with simultaneous equations.
The arithmetic calculations in Paper 1 also proved challenging for many candidates. Teachers are advised to look for more opportunities for pupils to practise without the use of a calculator.
Pupils tend to perform poorly in topics covered early in the Intermediate 1 course, said examiners. Teachers should revisit areas such as finding the mean from a frequency table, and distance, speed and time calculations involving fractions of an hour, to improve retention of these skills.