Oops, it doesn't look like 'record for the biggest day' is a national day..

Other days

reading

Reading Day
eat what you want

Eat What You Want Day
pick me

Pick Me Day
donate your hair

Donate Your Hair Day
cuddle up

Cuddle Up Day
gum

Gum Day
bounce

Bounce Day
blanket fort

Blanket Fort Day
me

Me Day
first love

First Love Day