Midlothian Council took action after a parent complained that a teacher at Lasswade High School in Bonnyrigg made remarks about creationism during a physics lesson.
It was claimed pupils were told by teacher Leonard Rogers during a discussion on the Big Bang - the scientific theory explaining the origins of the universe - that people should stop putting faith in things that cannot be proven.
Adrian Smales complained after his daughter told him the nature of the comments. He then met with headteacher Alan Williamson.
Mr Smales said he was shocked when his daughter first told him the assertion was made during an S3 physics class. He said he was satisfied with the action taken after meeting the headmaster.
Mr Smales said: "I had a meeting with the headteacher and the deputy head of the school and it came to a good conclusion."
Mr Smales, a PhD researcher in biomedical informatics who formerly headed the Natural History Museum's IT department, said Mr Williamson had earlier said the teacher "did state he held strong creationist opinions to [the] class".
Mr Smales said pupils could "discuss [creationism] as part of candid religious dialogue to say these are other views in the world".
However, he added: "In a physics class the teacher is supposed to be teaching mainstream education.
"Creationism is not based in true, verifiable fact, which is what you are supposed to teach at S3 level."
The council took the unusual step of issuing a public statement saying that creationism is not part of the curriculum in Midlothian schools.
Education convener Lisa Beattie said the council made the move "after an incident involving a Midlothian science teacher".
The council confirmed the teacher made remarks about creationism to pupils leading to the complaint.
Ms Beattie said: "I want to make it clear that the teaching of creationism is not part of the science curriculum in Midlothian.
"I was keen to understand the background behind this complaint. I understand that the investigation is now complete and we have discussed this incident with the parent involved, who is supportive of our actions.
"Teachers understand that they do not promote personal views or beliefs in the delivery of the curriculum."
Details of the outcome of the investigation carried out by the education department are confidential and will not be disclosed, the council said.
Creationists believe that the world is only 10,000 years old and reject the idea of evolution.
The Scottish Secular Society said last week the Scottish Government should provide clear guidance on how religious ideas about the origins of life are taught.