Fun with history
Someone at the National Archives has gone through the WWI draft database and found the registrations from several celebrities, sports figures and politicians:
Notable Registrants of the WWI draft.
It includes some men I wouldn't have thought were that old at time of the first war, like Sam Rayburn, Adlai Stevenson. Here's Sam Ervin's card. Note the little tab in the corner that says 'tear off if registrant is of African descent'. Primitive database sorting.
Also interesting: the registration for Alvin York. He claimed an exemption from duty on the grounds "don't want to fight".