If your goal is to pay off your loans early, you don't have to refinance. You can simply pay extra on your student loans, making sure that any extra you send in is applied to the principal of your loans.
Refinancing the student loans into a new loan will save you money on interest, but over one year, it may not be a lot of interest.
Let's look at the numbers for taking two of these loans ($7k). For the sake of discussion, we'll assume that the average interest rate for these "higher interest" loans is 8%.
If you left the loans where they are and paid off the $7k in a year, it would cost you $307 in total interest. If, instead, you refinanced the $7k at 3% and paid them off in a year, you would only be charged $114 in total interest, a savings of $193.
Whether or not the refinancing paper work (and any fees) are worth the amount you will save is up to you.
The only other watchout I can think of when it comes to refinancing is that when you compare options, make sure that your new loan is paid off in the same time as the old loan would have been (or quicker). If you refinance at a lower rate, but take longer to pay off the loan, you would likely pay more interest despite the lower rate.