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

Other days

gallery

Gallery Day
singles

Singles Day
bounce

Bounce Day
martini

Martini Day
stress awareness

Stress Awareness Day
one

One Day
african immigrant and refugee hiv and hep awareness

African Immigrant And Refugee Hiv And Hep Awareness Day
raise awerness of zeus

Raise Awerness Of Zeus Day
artists

Artists Day
self appreciation

Self Appreciation Day