Wow Comics #23 features Mary Batson in deadly danger from the evil Doctor Dwarf, who is has put her in a death trap in a sawmill because she's friends with Mary Marvel!

Anyway, she is rescued by being whisked to the future by a group of youngsters who are trying to recruit Mary Marvel to help with their youth revolution. While they unaware that Mary Batson is, in reality, Mary Marvel, they are happy when she shows up. Their whole revolution revolves around the fact that the education system has recently been changed, and instead of going to a traditional school to learn and socialize like traditional kids, they are forced by their robot caretakers to take pills which implant the knowledge in them. Anyway, Mary Marvel gets "mental indigestion" because the knowledge pills cause overload because she already knows all of the stuff or something, and Doctor Dwarf shows up and takes over the robots, but in the end the kids get to go back to school.

The reason for posting this thread is that there is a bit of proto-Adventure #247 feel to some of this, particularly in the bits where Mary is learning about the wonders of the "future playground", with things like gravity belts for the kids to swim in the air. There's no Nine Planets Ice Cream Parlor or anything, but still, it kind of parallels Superboy/Supergirl getting introduced to the amazing future stuff in their respective introductions to the Legion. It's not too obvious a connection, but it does suggest that Binder, who I assume wrote this, had at least a germ of what would become "The Legion of Super-Heroes" in mind as early as 1944. The whole "youth revolution" plot reminds me more of the threeboot Legion than anything we'd actually see in Adv. 247, however. Still, kind of fascinating as a bit of a possible build up to the series we love.