This looks like your classic JC Higgins frame. Should be a balloon bike that inherited skinnies at some point in its life. Rims may be original since either tire fits on balloon rims. Hodgepodge of parts otherwise; fenders are universal middleweights, chainring, guard, seat, stem, fork are all parts that were probably laying around to make a rideable bike. Definitely worth 15$ though! Perfect build material.