Don't forget you can also get discount as an NUS Extra card member - and you don't need to be 25 or below! Just log into your NUS EXTRA account for the discount code.
What if I'm over 25 but I have a railcard being a full time student?
Also you can get a household membership for £10 good for 2 adults living at the same address plus any children travelling with you if you have a family railcard using discount code 'ATOCJF-13'
Wow! Great discount