Its report Successful Science found that in 2010 around 12,000 more students than the previous year were awarded the top grades of A* and A in science GCSEs. This is an increase of 24 per cent.
Factors include the introduction of separate GCSEs in biology, chemistry and physics in 2006, which has given pupils a greater choice of subjects to fit their individual interests.
However, in primary schools Ofsted found that there was a lack of specialist science expertise among teaching staff to sufficiently challenge more able students.
A statement from Ofsted found the situation in primary schools "reflects less effective professional development in primary science, which means some teachers do not have the necessary understanding of scientific enquiry skills and physical sciences".
Ofsted chief inspector Christine Gilbert added: "This report highlights what the best schools are doing to ensure science courses prepare pupils for continuing education, training and living in a technological society."
Christine Blower, NUT general secretary, called for a level playing field across secondary and primary schools in training opportunities for teachers wanting to specialise in science.
She said: "There does need to be far greater access to science-specific continuing professional development for primary school teachers who are less likely to have a science background."
A link to the report will follow shortly.
