The school was one of many in the Hunter that marked Book Week this week by asking children to dress up as their favourite book character for a parade.

Principal Samantha Van de Mortel asked parents not to send children to school on Wednesday as witches and warlocks because it was inconsistent with school values.

She said it was a standing policy because the school felt it was not in line with its Christian ethos.

‘‘We just don’t believe that’s something we want to promote. We promote a Christian focus,’’ Ms Van de Mortel said.

She said the parade was a primary school event that was also open to students’ younger siblings and they were concerned many retail costumes were quite gruesome.

‘‘Frankly, we do not want any of our younger students or their siblings feeling frightened, intimidated or uncomfortable during any school activities,’’ she said.

While witches, warlocks and Harry Potter characters were out at the Medowie school, the characters allowed in the parade included Anakin Skywalker, The Mad Hatter and the Gingerbread Man.

Ms Van de Mortel said the Harry Potter series, which is about witches and wizards, was not available in the school library because it had been the subject of many international debates.

It topped the list as the 10 Most Challenged Books of the 21st Century by the American Library Association.

‘‘Medowie Christian School respects the right of parents to make decisions on whether or not to allow/encourage their child to read material,’’ Ms Van de Mortel said.

‘‘In respecting that right [we] do not stock books from the Harry Potter Series, or indeed other titles, which are the subject of polarising public discussion.’’

Medowie mother Bobbie Antonic, whose children do not attend the school, raised the issue on social networking site Twitter and said she was concerned it was censorship.

‘‘I was just blown away by it. It’s just bizarre,’’ she said.

‘‘Books are not reality.’’

Medowie Christian School Parents and Friends Association manager Lisa Taylor said from a parent’s point of view the prohibition was ‘‘no big deal’’.

‘‘In the lead up to Halloween the shops are full of so many grotesque, frightening costumes and I’ve got two little boys,’’ she said. ‘‘It’s supposed to be a celebration of literature.’’

She said parents were happy the school library did not send students home with books that could force a topic up for discussion.

‘‘I would like to be able to make that choice for my own kids,’’ Ms Taylor said.