Oops, it doesn't look like 'nose picking day' is a national day..

Other days

boba

Boba Day
kale

Kale Day
cat girl

Cat Girl Day
polyamory

Polyamory Day
bow tie

Bow Tie Day
lash

Lash Day
get funky

Get Funky Day
blanket fort

Blanket Fort Day
boyfriend

Boyfriend Day
reading

Reading Day