Budding performers in the US will be hoping a peculiar back-to-school exam will help them be on song this year.
A special camera allowed theatre students at a college in Seattle to see their vocal chords as they sang.
The idea is to identify any irritation or tensions in the chords so that any problems can be dealt with before they get too serious.
It lets the students from Cornish College of the Arts have an inside-out view of a part of their body that will get a lot of use in the coming years.
The camera, a stroboscope, emits light pulses slow enough to capture the vocal chords moving.