Explosive ventures kindle pupils' interest in the subject, writes Adi Bloom.The opportunity to mess around with liquid nitrogen or to set fire to hydrogen balloons can inspire pupils to take a new-found interest in science.
But the pressures of the national curriculum mean that many teachers struggle to justify the usefulness of such off-site experiments.
Ed Balls, the Children, Schools and Families Secretary, has said that out-of-classroom learning would be a key part of his Children's Plan.
But academics from London Metropolitan University believe that there are significant barriers still to be removed. They spoke to teachers at 325 primary and secondary schools about the advantages and disadvantages of out-of-classroom science learning.
Most teachers said that pupils had participated in several off-site activities over the last year. Teachers enthused about the benefits of these activities, almost all claiming that they should be motivational, rather than directly educational. A primary teacher told researchers: "I am more interested in my pupils being entertained by science, rather than educated."
Others referred to the "wow factor"of observing experiments that cannot be carried out in the classroom - like setting fire to hydrogen-filled balloons.
Primary teachers welcomed the opportunity to work with subject specialists. One said: "I am a jack of all trades. I am master of nothing, really." Expert speakers could also serve as role models, proving that women and ethnic minorities can also wear white coats.
But teachers stressed the number of barriers that stand in the way of off-site visits. Many complained about the limitations imposed by the exam-filled curriculum. One secondary teacher said: "We're completely governed by examinations these days."
Several said that they were obliged to find links between the curriculum and the proposed trip, in order to justify it to parents and senior management.
Others spoke about practical difficulties, such as the cost and time involved. One referred to parents who did not want their children to travel on the London underground after the bombings in 2005. Another believed that all but the most high-performing pupils were easily distracted outside the classroom.
The researchers agree with Mr Balls: they are keen for out-of-school activities to supplement classroom learning. But until the significant barriers are removed, these activities will continue to be viewed as an additional benefit, rather than an integral part of science education.
And teachers themselves need to be persuaded that out-of-school learning does not undermine classroom authority. The researchers insist that out-of-school learning is often redundant without classroom follow-up.
"There may be teachers who are reluctant to accept the limitations of the classroom," they said. "It may be that some are using practical excuses as a convenient excuse to mask this reluctance.
"When teachers see out-of-classroom learning as providing something very different from the classroom, there is a danger that it is seen as something separate and different. Taken to an extreme, it could be caricatured as 'outside for motivation, inside for learning'."