More young people, particularly girls, are studying science to age 16, but fewer are taking A-levels.
The problem could be solved by increasing the subjects studied in the sixth form to five, and increasing the length of the school day for years 12 and 13, says a report commissioned by the Engineering Council, and published this week.
The Impact of Double Science, by Professor Alan Smithers and Dr Pamela Robinson, of Manchester University's Centre for Education and Employment Research, says one way to overcome the poor uptake of A-level science is to improve the links between GCSE and A-level.
Compulsory science up to age 16 has led to a dramatic growth in science GCSE entries. Double science entries, in particular, have gone from 22.3 per cent in 1989 to 82 per cent now, says the report.
The objective of equally involving boys and girls has almost been achieved, say the researchers. In 1980, only 10.9 per cent of girls took physics to O-level, but by 1993, 65.2 per cent were taking physics GCSE or double award science.
Bridging the gap between GCSE and A-level could be helped by separate recording of performances in biology, chemistry and physics as part of the double award.