Oops, it doesn't look like 'state challenge opening day' is a national day..

Other days

unicorn

Unicorn Day
polyamory

Polyamory Day
girl friend

Girl Friend Day
bow tie

Bow Tie Day
first love

First Love Day
lash

Lash Day
gum

Gum Day
singles

Singles Day
ruby

Ruby Day
promposal

Promposal Day