Federal Student Loans
The Free Application for Federal Student Aid, known as FAFSA , requires both entrance and exit “exams" for students to determine that they understand the terms of their student loans. Part of the terms delineate when to start paying college loans back if you quit or paying back college loans after you graduate. You may also choose from a number of repayment plans, depending on the type and amount of your student loan. For instance, the standard student loan repayment plan requires a minimum monthly payment of $50 over a period of 10 years. 
Generally, according to the FAFSA site, the federal student aid program offers borrowers specific grace periods for repayment, depending on the type of your student loan. The grace period begins based on three criteria: if you quit, if you drop below half-time status, or after you graduate. The grace periods prior to beginning repayment are as follows, based on the type of loan:
Federal Stafford Loan: 6 months
Federal Perkins Loan: 9 months.
PLUS loans: within 60 days after final disbursement; HOWEVER, a graduate student, or a parent who is also a student enrolled at least half-time, may defer repayment for 6 months. In addition, for initial disbursements made on or after July 1, 2008, borrowers may be eligible for an extra 6 months deferment. 
If you filled out a FAFSA to receive your college loans, then you can review your financial aid paperwork to locate the loan repayment terms. You can also find these terms online at the FAFSA site, accessed with the designated personal PIN that FAFSA assigned to you. In addition, you may choose to discuss terms with the financial aid representative from your college or university if you have further questions or need clarification.
The most important point to keep in mind: begin repaying your student loan on time and maintain timely payments. Defaulting on your student loan carries serious consequences. The federal student loan program does allow for a deferment or forbearance if you encounter problems paying back the loan, but you must inform them of your circumstances, and then abide by the modified repayment terms.