Neighbors called the police when Buchman's home began to give off what officials described as a "god-awful" stench.
Police entered the home with a search warrant and arrested the 53-year-old, whose class will have a substitute teacher until Buchman "resolves his personal matter," a school rep said.
Buchman's neighbor, Forest Long Sr., told the Los Angeles Times that he had kept to himself since his mother died three years ago.
"Maybe he became lonely," Long said.
Police also found mice and rats in the home.
"There are all forms of decay," said Sondra Berg, from animal services at the police department. "From skeletons to just dead in the last few days. There is an infestation of rats and mice. They are running loose all over the house. There are rats and mice in plastic storage tubs that are actually canabalizing each other."
[LA Times, NBC Los Angeles]