- Dan Curtis Johnson
- Carlo Barberi
- Wayne Faucher; Juan Vlasco
- Pat Garrahy
- Dave Lanphear; Clem Robins
- JLA [as JLA, Jr.; Aquaman [Arthur Curry; as Aquaboy]; Batman [Bruce Wayne; as Batboy]; Captain Marvel [Billy Batson]; Flash [Wally West; as Kid Flash]; Green Lantern [Kyle Rayner]; Martian Manhunter [J'onn J'onzz]; Plastic Man [Eel O'Brian]; Red Tornado [John Smith]; Steel [John Henry Irons]; Superman [Clark Kent; as Superman, Jr.]; Wonder Woman [Diana; as Wonder Girl]];
JSA [as JSA, Jr.; Black Canary [Dinah Lance; as Crybaby]; Dr. Fate [as Li'l Fate]; Flash [Jay Garrick; as Golden Age Kid Flash]; Green Lantern [Alan Scott; as Teen Lantern]; Hawkgirl [Kendra Saunders; as Hawkbaby]; Hourman [as Hourbaby] (android); Star-Spangled Kid [Courtney Whitmore; as Starwoman]; Wildcat [Ted Grant; as Wildbrat]];
Old Justice [Doiby Dickles; Merry, Girl of a 1000 Gimmicks [Merry Pemberton]];
Young Justice [Impulse [Bart Allen]; Robin [Tim Drake]; Secret; Wonder Girl [Cassie Sandsmark; as Wonder Woman]; Superboy [as Superboy, Sr.]];
Point Men [Blank Slate; Blockade; Gray Lady; Serpenteen; Short Cut];
Ace Atchinson; Anarky [Lonnie Machin] (adult version); Deadman [Boston Brand; as Deadboy]; Lagoon Boy [as Lagoon Man]; Stripesy [Pat Dugan]; Wizard Shazam; Amazo (teen version); Klarion; Teekl (Klarion's cat)
- After being mistaken for Young Justice by frightened adults, the JLA Jr. escape to their headquarters to figure how to get back to normal. At Captain Marvel's suggestion, they seek out the wizard Shazam to cure them, but to no avail. Regrouping with the adult teenagers and the young adults back at the Young Justice Cave, all the heroes decide to solve the age problem individually.
- Happy Harbor; Sins of Youth; teleport pad; Watchtower
This issue immediately follows the events of Sins of Youth: Young Justice (DC, 2000 series) #1.