Back to basic blockplay perhaps, for these "blox" are closer to traditional blocks than have been many of my recent subjects. They are sort of a cross between Lincoln Logs and classic building blocks.
I will happily attest that although the corners do interlock in a manner, that provides no extra stability and does not dramatically aid in alignment. I shifted the cabin slightly out of plumb while moving its baseboard for the photograph, and probably spent more time getting it straight again than it took me to build it in the first place.
Bizzy Bilding Blox are an American product of the World War II years. Materials shortages and the conversion of many toy factories to war production created an opportunity for the Timmerman Manufacturing Company of Hibbing, Minnesota. It is the box art, not the blocks, that give away the era.
I will argue in favor of their educational value as a construction toy, but as for spelling ...