Scientists agree practicals are vital
Science teachers are doing fewer practical experiments because of the demands of the curriculum, tests and badly behaved pupils, a poll suggests.
Online research among 1,300 teachers by the government-funded Science Learning Centres found 96% said they faced obstacles to doing practical lessons.
Two thirds blamed pressure from the curriculum while four in 10 blamed the demands of testing and marking.
Pupils' behaviour was cited by 29%, and one in four blamed a lack of equipment.
Only one in 10 said health and safety fears were an issue.
Director of the National Science Learning Centre Professor Sir John Holman said: "Learning science without practicals is the equivalent of studying literature without books.
"Experimental evidence is the mainstay of science and the UK has a very strong tradition of scientific practical work in schools.
"It concerns me that, for a range of reasons, many teachers currently feel unable to dedicate as much time to practical work in the classroom as they would like.
"Activities such as ripple tanks, dissection and microbiology, which were once to be found in school science labs up and down the country, are becoming endangered species."
The survey suggests that time for experiments falls as pupils go up through secondary school, the Science Learning Centres say.
While 63% of Key Stage 3 teachers (teaching 11 to 14-year-olds) said they spent 40% of their teaching time on practical work, 43% of Key Stage 4 teachers said the same and just 28% of those teaching over-16s did so.