How can the teaching in question be found in or derived from the deposit of faith? Where is it in Scripture? Where is it in the fathers? Is the teaching implied by another teaching?
What the Church holds
What the Church holds . . .
The topic of the paper (what the prospectus is laying out) should be able to be formulated in the form, “The Church teaches that . . .”; So it should be a specific proposition that the Church holds, (e.g., “Mary is mother of God” or “Mary was conceived without original sin”) rather than a general topic (e.g., Mary). You should be careful, as you write your paper, to be sure it stays on topic.
As part of showing what the Church teaches, the paper should explain any difficult or easily misunderstood phrases in the teaching. (e.g., if one is explaining that “Mary was conceived without original sin” it would be helpful to explain briefly the Church’s understanding of original sin).
Here is a good place to bring up Magisterial statements that actually show, in the Church’s own words, what the Church teaches.
Also, the Church’s teaching is often most clear when it is rejecting or condemning theories that it holds are incompatible with the faith. The Church is often happy to let theologians hold their theories and tends to only offer definitive teaching when someone advances a theory that the Church holds is error. So, in clarifying what the Church holds, it is often just as important to look carefully at what the Church doesn’t hold. So consider any related condemned positions.
Why the Church holds it . . .
Whatever the Church teaches, she teaches because she holds that it is somehow connected to the deposit of faith. So how can the teaching in question be found in or derived from the deposit of faith? Where is it in Scripture? Where is it in the fathers? Is the teaching implied by another teaching?
As you write your paper, be sure to stick to the purpose of the paper: Explaining clearly what the Church teaches, and why it teaches what it teaches. I have found that students sometimes treat these papers as opportunities to explore their personal musing on life, the universe, and everything. Such musing may or may not have much value, but in either case sharing them isn’t the purpose of the paper.
Also be especially careful to be precise and accurate in describing the Church’s teaching. This is not the place for sloppy paraphrases that kinda-sorta give the general idea. This the place for precision of language.
As to sources,
In order to complete the assignment, the paper must actually make use of five sorts of sources:
(1) at least one relevant patristic source
(2) at lease one relevant passage of scripture
(3) at least one relevant magisterial source
(4) any relevant passages from either the Catechism of the Catholic Church or the Roman Catechism (I expect that you will find at least one)(5) at least one relevant and approved systematic work of theology.
‘Relevant’ should be taken to mean that the specific passage being used directly relates to the topic of the paper.