How it's played:
People choose squares in a 10x10 grid. When the deadline for the pool passes, random number from 0 to 9 are assigned to each column and row. The columns numbers represent the last digit of the score for one team and the row number represent the last digit of the score for the other team. At the end of each quarter, the winner for that quarter is the person whose square matches the column and row corresponding the score for that quarter.
Example:
With one team assigned to the rows and the other team assigned to the columns, if the score is 24-17 at the half, with the 24 points belonging to the columns team and the 17 points belonging to the rows team, the halftime winner would be the person with square column 4, row 7 on the grid.
This is played the same way for each quarter so all participants have a chance to win in each quarter. If there is a scoreless quarter, it is possible for the same person to win twice.
Reason to play:
This kind of pool makes watching the Super Bowl or any sporting event more fun because rather than cheering for a single team, you are hoping that the teams score in a certain way that selects your grid square. For example, a team deciding to go for the end zone before the half versus running out the clock could affect the winner for the halftime score.
Super Bowl vs. Custom:
These are the exact same game except in a Custom Squares Pool, you specify the names of both teams when you create the pool, you set the deadline date and time, and you enter the scores yourself. In a Super Bowl Squares Pool, the teams are already selected, the deadline can be customized to various times before the kickoff date/time, and scores will update automatically.