Aye! People!
I see alot of confusion at the tagboard.
Hope I can fix it or something.
Dont know if you guys like my idea of what.
But Im trying to help out okay!
So hear me out.

My suggestion: (suggestion! ITS NOT SETTLED!)
Open your eyes BIG ENOUGH TO SEE !
Group 1 :Register 1 , 2 , 3 , 4 , 5 , 21 , 22, 23, 24, 25.
Group 2 : Register 6, 7, 8, 9, 10, 26, 27, 28, 29, 30.
Group 3: Register 11, 12, 13, 14, 15, 31, 32, 33, 34, 35.
Group 4: Register 16, 17, 18, 19, 20, 36, 37, 38, 39, 40.

As you can see, the girls and guys are mixed,
Because the girls and guys need to be more bonded,
And some things the girls cannot do, (carrying heavy stuff), the guys can do.
Group 1 : Bring disposable stuffs ( plates, cups, forks, spoons)
Group 2 : Get the BBQ stuffs ( order and get )
Group 3 : Bring along food ( Chips, sodas , anything also can)
Group 4 : Eerm, planners? You guys think what to do for the whole day. So that we will not get sianed. Like maybe think of some class games, cycling or whatever.

Like i said
THIS IS A SUGGESTION.
YOU GUYS ARE FREE TO REJECT IT IF YOU DONT LIKE IT.