Many of these appear to be from "The great international paper airplane book", which lists the top contestants from the first International Paper Airplane contest (1967?). It's a great book and I highly recommend it.
I was obsessed with this book in 1st through 3rd grade and must have checked it out from the school library 50 times.
Just picked up a used copy from Amazon 30 seconds ago; thanks for reminding me.
Wow that's the book I was thinking of when I mentioned Foghorn Leghorn. The little genius kid makes a plane from that book.
I bought this book at a garage sale when I was in 3rd grade and I became obsessed with building and flying them. My neighbor made a paper plane years before and out of curiosity I unfolded it and couldn't put it back. I was devastated but was too shy to ask him to show me how or make another. It was in this book that I found the plane he made me and I learned how to fold it and happiness ensued for years.
Some clearly well-built planes there, and some that definitely would only fly once. For some reason, I thought of Foghorn Leghorn.
https://www.youtube.com/watch?v=xDjDv-RGC1Q