I picked up a copy of this a while back and placed it in one of bookshelves to see how long it took my 12 year old to find it. Found it in his room about two weeks later..
I would recommend reading up on what the ATF considers a "destructive device" or "any other weapon" before home building any cannons or similar things.
https://www.google.com/search?client=firefox-b-d&q=atf+defin...
An ignorant but technically motivated person can also "accidentally" build an NFA form 1 or form 4 firearm by making a short barrelled rifle without the appropriate tax stamp, just by combining pieces together. Or by doing something like putting a vertical foregrip on something that is legally a pistol. Or by making a home-made silencer. And so on.
I recently found this book in a used bookstore. I wish I had owned a copy when I was a kid. I’m thinking about giving one to my nephew, but I’m not sure what his parents would think.
There's also The Dangerous Book for Boys
This was one of my favorite books growing up
I made the potato cannon from this book as a teenager. It was made of a PVC chamber for the propellant and a narrower ~potato-sized PVC pipe with the end filed to be sharp so that a potato would be trimmed down to create a potato slug with no air gaps around it.
The propellant was hairspray. You'd unscrew a threaded PVC end-cap from the back of the cannon, spray the hairspray into it, screw the cap back on, and ignite with a flint striker from the outside.
It was a really cool device.