The rain of dandruff that comes off your head when you scratch.
When Joe scratched his head, the flake shower that came off him rivaled that of Ally Sheedy in the Breakfast Club when she made it snow on her drawing.
A hardo is a person who tries extremely hard at everything. Most times a hardo will try very hard at things that do not require excessive effort. For example, sports practices, gym class, etc.
Wow did you see Jack at practice today? What a hardo!