As you know, I too am a fan of school secret society comics. Thanks for collecting these stories for us. The artwork changes radically between stories. The first uses the somewhat stodgy heavily-crosshatched style I associate with this sort of comic (stodgy, but I like it), while the second takes a much more open approach, as if drawn for color.
The secret society concept must have struck a chord with readers back in the day. There seem to have been lots of them--and you say they date back to the 1930s! Do you know if The Green Feather was the first?