Jacob Two-Two and the Puzzling Portable Jacob Two-Two : Season 4 Episode 10

An off limits portable classroom and the sudden appearance of a muscle-bound supply teacher with a monotone accent (that strangely resembles Arnold Schwarzenegger) adds up to Jacob being the ‘chosen one’ who is destined to save all of mankind from some terrible future fate. Renee attempts to get the boys to say "personkind" instead of "mankind."