scratch your head
idiomPart ofscratch
scratch your head — idiom
1. to think hard about something because you find it confusing, surprising, or diff
1.idiom
Definition
to think hard about something because you find it confusing, surprising, or difficult to understand
Example
The teacher scratched her head over Ella's unusual answer to the maths problem.
Scientists are scratching their heads over why the birds changed their migration route.