This invention, which appeared in each of the Alvin books, was designed to keep The Pest out of Alvin's room. From a young age, The Pest had figured out how to defeat it. Unfortunately, Alvin usually forgot that it was set, which resulted in Shoie as the primary victim.
"As usual, when Alvin
got to his room he was thinking so hard about something else that he forgot
to turn off the Foolproof Burglar Alarm. The instant he opened the
door a bell began to clang, all the lights in the room flashed on and off,
and a boxing glove on the end of a long wooden arm came whistling across
the doorway. Alvin ducked in time, but the glove caught Shoie squarely
in the ear."
