Oops, it doesn't look like 'post every single picture or video you have of you and all your friends on snapchat day' is a national day..

Other days

Azonto Is Acceptable Day

Chocolate Milkshake Day

Nail Polish Day

Lost Sock Memorial Day

Tell A Fairytale Day

Mean Girls Day

Ponytail Day

Aloxolt Day

Pumpkin Day

Youth Day