Oops, it doesn't look like 'block it out day' is a national day..

Other days

slime

Slime Day
camera

Camera Day
fiancee

Fiancee Day
bubble bath

Bubble Bath Day
gum

Gum Day
get funky

Get Funky Day
ruby

Ruby Day
frozen yogurt

Frozen Yogurt Day
comfy

Comfy Day
special education

Special Education Day