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

Other days

nae nae

Nae Nae Day
youth

Youth Day
bounce

Bounce Day
singles

Singles Day
special education

Special Education Day
gum

Gum Day
slime

Slime Day
bow tie

Bow Tie Day
lash

Lash Day
frozen yogurt

Frozen Yogurt Day