Oops, it doesn't look like 'look dumb dennaho day' is a national day..

Other days

stud

Stud Day
ponytail

Ponytail Day
slime

Slime Day
cat girl

Cat Girl Day
one

One Day
gum

Gum Day
boba

Boba Day
bow tie

Bow Tie Day
brow

Brow Day
raise awerness of zeus

Raise Awerness Of Zeus Day