Football squares is the most popular way Americans gamble on the Super Bowl.
For the uninitiated, football squares is a grid of 10-by-10 boxes on a sheet of paper or a computer screen. Participants pay a certain amount per square and put their names or initials in random squares without knowing which numbers they’ll get for each team. The teams are often shown with one at the top of the page and one on the side. When the grid is filled out, the organizer of the pool randomly selects the numbers — 0 through 9 — for each team and puts them on the grid.
Most pools will have a prize for the score at the end of each quarter, often with a bigger prize for the final score. Winners are determined by lining up the last digit of the score of the team listed on the top of the sheet and the last digit of the score of the team listed on the side of the sheet.