Pupils from the Lincoln Elementary School in Glendive, Montana, have been going to the Glendive Dinosaur and Fossil Museum for their field trips the past seven years.

This year, however, there will be no such visits to this creationist museum after a prominent church-state separation group threatened to file a lawsuit against the public school for supposedly violating a provision in the Constitution that prohibits bias towards a particular religion.

The separation group Americans United for Separation of Church and State (AU) sent a letter to the administration of the public school asking officials to put an end to field trips to the museum operated by the Christian group Foundation Advancing Creation Truth (FACT).

The museum puts on display fossils and artefacts, and advocates a biblical worldview about creation.

The group argued that these field trips run counter to the Establishment Clause of the First Amendment to the US Constitution.

"[The courts have] consistently and unequivocally held that religious views on the origins of life, such as creationism, 'creation science,' and 'intelligent design,' cannot lawfully be advanced by the public schools as alternatives to the scientific theory of evolution," AU's letter to the Lincoln Elementary School stated.

The letter prompted the school to cancel a scheduled museum field trip for 100 third graders. The pupils' parents have already agreed to the trip through consent forms submitted to the school.

Principal John Larsen nevertheless said that it is the school's understanding that the Glendive Dinosaur and Fossil Museum displays a secular presentation for public school students that is void of any mention of creation or religion.

Robert Canen, vice president of FACT, also maintained that the museum "stays away from any discussion of the Bible for public school tours."

"While our museum is based on biblical history and all of our exhibits are set in that context, we provide a tour that focuses on the fossils displayed in the museum and the characteristics of those fossils," the museum official said.