To structure your IA paper, consider the following questions and guides.
Introduction
What is the background to your topic, and where/how is your topic an opportunity for mathematical exploration?
Rationale
Why did you choose your topic?
Aim/Purpose
What would you like to achieve from your exploration?
Your purpose of the research must be clear, focused, and show enough evidence supporting your personal engagement.
Main Body
What Math are you using in your topic?
If you are using any formulas/theorems/propositions/etc., how are those derived?
Is there any proof or history to discuss?
Look at different perspectives on the problem, and discuss their respective merits and outcomes.
Describe the methods, followed by the investigation.
Record the results (tables, lists, values, etc.), analyze the results (graphs, diagrams, calculations, etc.), and form conjectures.
Conclusion
What did you learn?
What were your limitations?
What areas are there for further exploration and application of your research?
Reference
The paper should include a detailed bibliography.
Include any sources and direct quotes you referenced.