The Easter mufti day. Entry fee: one Easter donation — eggs, bunnies, baskets. One school day fills the whole prize table for the cost of cellophane. The full trick.
Draw it at the Hat Parade. The audience is already there, the winners are collected on the spot, and next year’s tickets sell themselves on the memory.
Start selling week 6 of term 1. Three weeks of selling beats six — scarcity is honest when the draw date is printed on the ticket.