I just realized I never explained why I'm calling this a "Not a Raffle" raffle.
A raffle is where you buy tickets for a prize, using -money-. Since there is money involved in the buying of tickets, there are laws that govern raffles.
Well, we're not selling tickets for money. This is a "contest" using acorns and no money is changing hands, so it's not really a raffle. It's a "not a raffle raffle".