mad dumb
Mad dumb is when you're so dumb you think your dumbness is actually smart and people just roll their eyes at you.
He tried to fix the printer by hitting it with a hammer. It broke. He was like, 'Now it’s fixed.'
She told her mom she was going to be a superhero. Her mom said, 'Okay, but wear pants.'
He ran into the school principal’s office and said, 'I came to fight you.'