There are calls for a school to be investigated after promoting creationism and an evangelistic Christian course.
The National Secular Society (NSS) said it had obtained images of wall displays at Llanidloes High School in Powys showing marine life and the solar system beneath lines from the Bible such as “great are the works of the Lord” and “God created the creatures of the sea”.
The NSS is calling for a ban on teaching creationism in schools in Wales, saying "it undermines teaching about evidence-based theories such as evolution".
The Welsh government said community schools "are not permitted to have a religious leaning".
While teaching creationism as a scientific theory is banned in England, the promotion of creationism is not prohibited in schools in Wales.
The NSS claims the promotion of creationism at the school is being led by head teacher Daniel Owen, who is also an elder or spiritual leader at an evangelical church in Newtown, about 14 miles from Llanidloes.