Oops, it doesn't look like 'treasure any day' is a national day..

Other days

slime

Slime Day
lumpy rug

Lumpy Rug Day
hoodie

Hoodie Day
cursing

Cursing Day
lisp

Lisp Day
self appreciation

Self Appreciation Day
bow tie

Bow Tie Day
buddy

Buddy Day
get funky

Get Funky Day
camera

Camera Day