It would all depend on what the interest rates are on the loan. There are several repayment plans available and you can set you repayment to be anywhere from 10 to 30 years. There is even a plan in which the remaining amount of your loan is forgiven if it takes more than 25 years to pay back. Check the <a href="http://www.ed.gov/prog_info/SFA/StudentGuide/2001-2/direct.html" target="_blank">Student Guide</a> to Stafford loans.
So you have some idea, I have listed some interest rates, re-payment periods in years, and the repayment amount for $100,000 loans.
6%, 10 years, $1110 per month
7%, 10 years, $1161 per month
8%, 10 years, $1213 per month
6%, 15 years, $844 per month
7%, 15 years, $899 per month
8%, 15 years, $956 per month
6%, 20 years, $716 per month
7%, 20 years, $775 per month
8%, 20 years, $836 per month
Hope this gives you some idea of what to expect.