Bob Arbogast (1927-2008) was an actor, voice artist, writer, and radio personality who worked on Sesame Street inserts. In the abandoned "The Man from Alphabet" series, Arbogast played Teacher, the Man's boss. He was heard in several animated inserts, often narrating poems about letters or as nasal-voiced meek types, and occasionally scripted such segments.
Arbogast had worked with "Man from Alphabet" co-stars Gary Owens, Jim Thurman, and David Ketchum on the animated series Roger Ramjet, where he gave voice to Ma Ramjet, General G.I. Brassbottom, and other characters. Other voice credits include The Smurfs, The Jetsons, Hot Wheels, and Galtar and the Golden Lance. On the CTW math series Square One TV, he was heard as cartoon character Mr. Beasley and appeared on-camera in a "Mathnet" episode.