Since the mid-1990s, the proportion of 12th-grade pupils who believe smoking a packet or two of cigarettes a day carries a great risk has risen by about ten percentage points.
ECONOMIST: But efforts to warn people off drugs are still too timid
Mr Andrews came under fire last summer when he ordered the WJEC board, which sets most of the GCSEs taken by Welsh pupils, to re-grade English language exams after the results were published.
BBC: WJEC says Leighton Andrews could damage Wales exam system
Welsh Education Minister Leighton Andrews ordered the WJEC exam board to re-grade papers, saying the way that grade boundaries were set had been unfair to Welsh pupils.
It resulted in a slight fall in the number of pupils achieving at least a C-grade, from 65.4% to 63.9% this summer.
The age of pupils can be another determining factor: under-age pupils are more likely to repeat a grade, while over-age pupils tend to leave school early.
Education Minister Leighton Andrews came under fire this summer when he ordered the WJEC board, which sets most of the GCSEs taken by Welsh pupils, to re-grade English exams.
The English Baccalaureate was introduced as a measure of school performance, appearing in league tables, and showing the proportion of pupils achieving GCSEs grade C and above and some AS-levels in specified key subjects.
This will aim to bring all pupils up to at least a C grade at GCSE, but for pupils who cannot achieve this the government is proposing "high-quality alternatives", which will be identified after a consultation.
Most of the controlled assessment work was submitted in the summer and when examiners saw evidence of over-marking, exam boards raised grade boundaries, leading some pupils to receive poorer grades than expected.
BBC: GCSE English: Teachers' anger over generous marking claim
They are threatening to seek a judicial review after thousands of pupils scored lower-than-expected results when grade boundaries were raised midway through the year.
Head teachers have claimed that English grade boundaries were manipulated downwards to ensure that the overall results did not increase - at the expense of individual pupils and their schools.
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