Personally, I kept my account as I have no monthly fees and I knew that I'd need it for some reason or another. I am VERY glad I decided to do this as it has been a godsend more than once. Check to see how your fees would work. I am sure you'll need it at some point or another.
As for student loans, I have Sallie Mae and I can pay mine online using my US bank account (see? told you it was handy) SM has a good online site that lets you do everything that way. I recommend transferring money using either paypal or some other method (bankers draft to the US, etc) and then pay that way. Some UK banks do transfers to US accounts but fees are high. You would need to ask in advance on that one