Ian Richardson, HMI specialist adviser for science, is expected to tell the Association for Science Education conference that primary teachers have lower expectations of pupils in science than in other core subjects.
Teachers' command of the subject, teaching methods and lesson planning are no better than satisfactory in a third of primaries, a much higher figure than for English or maths.
Mr Richardson will call for better leadership and management of the science curriculum in primaries, as well as planning to allow pupils to undertake scientific enquiry.
Ofsted evidence shows secondary vacancies in science are higher than in any other subject and this is damaging teaching and limiting pupils'
Mr Richardson is expected to say today: "There is a real need for pupils to be engaged in relevant and exciting science. Pupils' attitudes to science are generally good, but are less positive where they are not actively involved through scientific enquiry, making decisions and expressing views.
When teaching methods are unvaried and repetitive they become disengaged."
Teaching is also hampered by inadequate facilities with one in six schools having unsatisfactory laboratories and classrooms.