Banks recognise that the average student is more likely to be overdrawn than in credit. That's why the main selling point with any undergraduate bank account is a large, free overdraft.
Banks also offer free gifts to entice you to open an account with them. These are useful but the main benefit of a student account is that interest-free overdraft.
Existing students can switch their account to get the same terms as others in the same year of study. If you're a second or third year student, be sure to check the new account at least matches what you're already being offered (or have) in terms of a 0% overdraft.
Check what's on offer and make sure you choose the best account by reading the Money Saving Expert guide to student bank accounts.
For more information on bank accounts or if you have a problem with your bank contact your Students' Union's Advice Centre.