Whoa! That's a big one! Are we talking about a child's project? This sounds more like a graduate-level project. What body? The human body? Which minerals (there are many, many)? If you are talking about a child's project here, I'd recommend he/she simply look up and report on previous research on the matter. I pasted a web link about the effect of the mineral iron in the body. Your child can look for the effect of copper, selenium, magnesium, manganese, lead, and other minerals.
It is quite hard topic for a research paper.
You have to search about tips and trick on that. But usually it is ordinary and your paper will be just like all.
Maybe better for you to pay someone to write a paper http://www.someonetowrite.com/?
It will be a very good decision, because you will definitely have perfect writer who knows your niche.
Firstly, you must be specific with the topic. Minerals, for example, is too broad. The body is also too broad. I can give you an example of the topic: The effect of mineral iron on child's body when consumed regularly.
Secondly, you must determine the purpose of you research. For example, to bring insight about the use of mineral iron in child physical development stage.
Thirdly, draw an outline. It's the blueprint of your paper.
First of all you need to decide on your content and decide what questions you would like to discuss. Those questions should be very interesting and catchy, so your research paper is interesting to read. Some of the steps of creating a research paper are described at https://writing.wisc.edu/Handbook/PlanResearchPaper.html and also at http://researchpaperwritings.net/ . One more thing you should remember that the research paper should be not very long however up to the topic.