The incredible teenager with a rubber body!
Bouncing Boy is the codename of Chuck Taine, a 30th-Century delivery boy.
Bouncing Boy gains the power of super-bouncing when he drinks a scientist's strange potion, mistaking it for soda-pop (Adv No. 301/2, Oct 1962: "The Secret Origin of Bouncing Boy!").
Bouncing Boy is a member of the Legion of Super-Heroes.
Supergirl first meets Bouncing Boy when she journeys to the future and is invited to join the Legion in May 1961 (Act 276/2: "Supergirl's Three Super-Girlfriends!").