A kitemark devised to help teachers find suitable school trip destinations has been awarded to a Christian zoo accused of promoting creationism.
Noah's Ark Zoo Farm in Wraxall, near Bristol, is among the latest organisations to receive the Learning Outside the Classroom "quality badge", developed by the last Government.
The zoo already runs sessions for more than 15,000 pupils a year from key stage 1 to A-level.
But it has attracted controversy for its views on evolution and creation, arguing that science has tried to "remove any notion of God from our understanding of life".
"This is unjustified and we look to put the case for a Creator across to those who wish to investigate," the zoo's website says.
It argues that while evolution has taken place, it cannot explain the origins of life. Elsewhere, the website challenges fossil evidence and quotes widely from the Bible.
The quality badge is designed to help teachers plan trips. Organisations have to demonstrate that they offer high-quality learning experiences and manage risk effectively.
James Gray, education officer at the British Humanist Association (BHA), criticised the Council for Learning Outside the Classroom (CLOtC), the educational charity that awards the badges, for its decision.
"It is entirely inappropriate that it should support an establishment that advances creationism and seeks to discredit a wide variety of established scientific facts that challenge their religious views," said Mr Gray.
"Teachers and parents look to the council for assurance that children will experience high-quality educational visits that meet the relevant government guidelines. Awarding this zoo a quality badge risks exposing hundreds of children to anti-scientific dogma."
The argument is the latest instalment in a long-running debate about the place of religion in science and what pupils should be taught about conflicting views.
But a zoo spokesman strongly denied that its religious beliefs form any part of its educational sessions.
"Our religious element is not forced on or taught to children in workshops, and thus we believe the BHA are misguided in their criticism," he said.
"We do not teach religious ideology in school workshops; these are purely based on accepted national curriculum teaching."
He said that the zoo accepts evolution as scientific fact, but looks to "open up discussion as to the extent of evolution and whether indeed everything can be traced back into a singular ancestral tree of life".
He denied that the organisation subscribed to a concept of creationism that excludes the role of evolution. He added that the sessions for pupils focus on biology, covering topics such as life cycles and habitats.
The Learning Outside the Classroom campaign was developed by the previous Government after the Commons education select committee investigated school trips in 2005.
The CLOtC, which was set up in April 2009, has awarded about 670 quality badges and counts Mick Brookes, general secretary of heads' union the NAHT, among its trustees.
Elaine Skates, its deputy chief executive, said that all places are carefully assessed before approval.
"We believe that an important aim of learning outside the classroom is allowing children and young people access to education that challenges assumptions and allows them to experience a range of viewpoints," she said.
- Original headline: Approved for school visits: the Christian zoo accused of backing creationism