Lyndon Bannon, head of RE, said the Bible was used across the curriculum, including studying the text in literacy programmes.
RE is one of the most popular subjects at the non-denominational secondary and this year more than a third of Year 10 pupils will sit the full GCSE.
Last year, 70 per cent of pupils at Woodchurch achieved an A* to C grade in RE, up from 47 per cent three years ago.
Pupils at the school are either Christian or of no faith. Mr Bannon said that in RE the Bible was used to support teaching about Christian festivals, the life of Jesus, Judaism and stories about the creation of the Earth. The text is also analysed in literacy classes.
But Mr Bannon said the Bible was also used critically, including searching for "the reasons for anti-Semitism", such as the portrayal of the crucifixion, and in GCSE courses children are encouraged to question the Bible.
"It is vital to the teaching of RE and, in this school at least, has not become marginalised in any way," he said.
Mr Bannon said teachers had to come up with imaginative ways to bring the Bible to life. "We might set them a research or problem-solving task using the text but it would be unproductive to ask them to read huge chunks of text.
"It is only really at GCSE when we might ask them to go away and read different sections of it, but that would always be with the aim of producing a set piece of work at the end of it," he said.