Captain Marvel/Shazam integrated into the DC Universe in 1987 in a miniseries by Roy Thomas. I have not had the luxury to read this miniseries, but I assume that Billy Batson was around 10 to 13 when that occured. Flash forward to the "A Lonely Place of Dying" storyline in the Batman and New Teen Titans books and you see the first appearance of Tim Drake who was also in a similar age range.

Roughly thirty years later and a lot has changed for the character of Tim Drake. Pre Flashpoint during Fabien Nicieza's Red Robin run Drake was college age. If Tim Drake and Billy Batson are similar ages then shouldn't Pre-Flashpoint Billy Batson also be college age? This kinda defeats the purpose of the character.

Obviously in New Fifty Two-Rebirth continuity, Tim Drake got slightly de-aged, but Billy Batson being in his late teens still is incredibly awkward considering the entire appeal of the Captain Marvel-Billy Batson dynamic is the contrast between the childishness of Batson and the adult characteristics of the Captain persona.

What's the explanation for this? What's the solution to this? How can you explain Captain Marvel being around when Wally West started his tenure as the Flash when he's basically been portrayed as a little kid all his history?