If you wish to reference a curriculum document as a publication independently of the website on which you accessed it, the APA style manual provides a broad category called gray literature. Gray literature does not specifically cover curriculum documents but is a suitable category. Examples include government and agency reports, codes of ethics, press releases, and so on. See Gray Literature.
The explanation and examples below relate to referencing curriculum documents on the Australian Curriculum website.
Curriculum documents on a website such as the Australian Curriculum site are challenging to reference because each document is broken up over multiple web pages and expanding web-page sections. In this case, you can choose to reference the location on the web page by heading and section.
The Australian Curriculum website also has a "Download content" feature that facilitates the PDF download of a curriculum document. The PDF document compiles the text elements of the curriculum but will not have all the interactive features available on the website. Reference the downloaded PDF document as gray literature.
In-text citation
This is a quotation from the Rationale of Understanding how English works, Year 9 English curriculum.
Reference List