a dinni ken
A dinni ken is like throwing your hands up and saying you're done with life.
'I dinni ken how to do this problem.', said by a kid who didn't even read the question.
'I dinni ken why I'm late.', said by a kid who was playing video games instead of getting up.
'I dinni ken what day it is.', said by a kid who hasn't checked his phone in a week.