As you research your appellate brief, you may find it helpful to look at briefs and other case filings from similar and/or related cases. The Federal Judiciary makes many filings available through its official service, Public Access to Court Electronic Records (PACER). PACER requires an account and charges a per-page fee for any documents accessed through its system.
As a law student, you have access to most PACER content through Bloomberg Law, and will not incur a fee for accessing the documents. Case filings can occasionally be found in Lexis and Westlaw, as well.
A docket sheet is a document that is kept in a case file at the courthouse. It gives a list of all papers filed and actions taken in a case. A docket sheet is a public document and can be inspected by anyone except in the case of juvenile and confidential matters.
Federal docket sheets are available through PACER and on Bloomberg Law. Bloomberg Law offers a series of video tutorials explaining how to find and search through docket sheets and other litigation materials.