Signing up to an online course to get a student discount card?

Hi I am interested in getting a student discount card but obviously one of the requirements is to be a student of course, I wondered if there were any online courses I could take like the many available on Groupon to get a card? I see there is totum and unidays for student discounts, I am not sure what one I would register for but could anyone help me in finding the right course in order for me to get a student discount when I next go shopping? Thank you