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

Other days

first love

First Love Day
tell a fairytale

Tell A Fairytale Day
book

Book Day
polyamory

Polyamory Day
blanket fort

Blanket Fort Day
lash

Lash Day
promposal

Promposal Day
pick me

Pick Me Day
stud

Stud Day
special education

Special Education Day