McClaren took charge in June but has overseen a dismal campaign in which the Magpies have won just six out of a possible 28 league games.
"Someone has to be accountable and decisions must be made," the NUFC Fans' Forum said in a statement.
"What Newcastle fans want is a team of 11 players in black and white shirts that understand their role to perform to their maximum -- week in, week out.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
"Our players frequently look jaded and our playing style often appears outdated. We lack organisation and the players continue to lack discipline. Whilst we have 10 games to go, fans cannot accept the current work ethic of the players."
(Reporting by Simon Jennings in Bengaluru; Editing by John O'Brien)
