Last month, Australian National University vice chancellor Brian Schmidt sent out a video Tweet that, by his standards, got a pretty big reaction. More than 22,500 people viewed his 54-second piece to camera.

The topic wasn’t one that might typically set pulses racing on social media: ATARs, the number between 0 and 99.95 that school-leavers are given, based on their final exam results, which universities use to select students for admission.