The Marvelous Inventions of Alvin Fernald by Clifford B. Hicks. The coolest book I've ever read. Like Alvin's room, mine was always full of junk and inventions. My dog's doghouse was full of more junk - she couldn't fit because of all my junk. Hubcaps, pulleys, chains, old shock absorbers, railroad spikes… If it was on a junk pile, it was fair game.
Disney made a couple Alvin Fernald movies for their Wonderful World of Disney TV show. I can't find these on VHS. If you know anything about these, please let me know.
Update, 1996\06\23: Mr. Hicks' son found this page and contacted me. My search for the tape is complete! I'm the happiest guy in the world! :)
Update, 1996\07\08: Mr. Hicks himself mailed me a letter!
Update, 2022\01\06: I finally bought and read Alvin's Secret Code. The book Codes and Secret Writing was mentioned, which is a book my brother had and I inherited as a kid. I stunk up our science classroom by trying one of the invisible inks that used a sulphur compound. I also found out we lost Mr. Hicks in 2010. David, Doug, or Gary, if you find this web page; my condolences. I just wanted you to know your dad is still one of my heroes, and his books are still being read.