I used to have a lot of children that turned up late for school in the morning.
So I started a raffle system. Each morning I’d take out raffle tickets to the children standing in line. I would start at the back and work my way forward. This meant that you had to be on time to receive a raffle ticket.
The tickets would then go into a box, and at the end of the week, the raffle would be drawn and a prize won. Children who were always on time had more chances of winning.