The watchdog said Kings Kids Christian School in southeast London didn't meet independent school standards because students aren't taught about scientific theories of earth's origin.
Ofsted reported that: "The school's curriculum does not meet requirements. Pupils do not study practical science or develop the skills to collect and evaluate scientific evidence.
"The creation story is taught in science and there is no evidence that pupils learn scientific theories about the origin of the Earth."
However, Nigel Steele, the school's spokesperson, told Premier if Ofsted was at the school for longer, it would notice that the school does teach different perspectives.
He said: "They do look at the evolutionary theory but they also cover the design aspect as well. We'd say actually the students have a broader education regarding origins."
"The school's next thing to do would be to create an action plan to meet those standards. It doesn't mean the school will be changing the curriculum; they will still be able to teach science from a design perspective. They will need to make it clear where they are bringing other perspectives in."
Oftsed did praise the school of 25 pupils for having excellent spiritual awareness.
Steele said that was a great encouragement for the school.
"It's a Christian school and it's a school that seeks to make Jesus the centre of all the learning. To be affirmed that the school is meeting those aims is clearly very positive," he said.
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