Answer: The student will have to get a replacement copy of her Naturalization Certificate. The application for a replacement Naturalization Certificate is here: https://www.uscis.gov/n-565
She needs to complete that fully. To avoid the fee, she needs to submit with the application a form I-912, which is the request for fee waiver. That form and instructions are at: https://www.uscis.gov/feewaiver
She will need to show that, “Your household income is at or below 150 percent of the Federal Poverty Guidelines.” (This is box number two on the form.) This likely will not be a problem since she is an unaccompanied homeless youth. A letter from your school documenting her homelessness will be a helpful addition to the application. If she fills out the application completely, she should get the waiver.
Since she’s requesting the fee waiver, she probably should do this by mail, rather than online. It is apparent that time is an issue for her financial aid, and the processing of these forms will take time. So we suggest letting the college financial aid office know she is requesting the copy, and even sending them copies of her replacement application and fee waiver form. Hopefully the office will be willing to give her a break on deadlines.