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

Other days

self appreciation

Self Appreciation Day
brow

Brow Day
kale

Kale Day
hiv awareness

Hiv Awareness Day
boy friend

Boy Friend Day
believe

Believe Day
bow tie

Bow Tie Day
hannah

Hannah Day
boba

Boba Day
gum

Gum Day