American football
Football games last for a total of 60 minutes in professional and college play and are divided into two-halves of 30 minutes and four-quarters of 15 minutes. High school football games are 48 minutes in length with two-halves of 24 minutes and four-quarters of 12 minutes. The two-halves are separated by a halftime period, and the first and third quarters are also followed by a short break. Prior to the start of the game, the referee and team captains for each team meet at midfield for a coin toss. The visiting team is allowed to call 'heads' or 'tails'; the winner of the toss is allowed to decide between choosing whether to receive or kick off the ball or choosing which goal they want to defend, but they can also defer their choice until the second half. The losing team, unless the winning team decides to defer, is allowed to choose the option the winning team did not select, and receives the option to receive, kick, or select a goal to defend to begin the second half. Most teams choose to receive or defer, because choosing to kick the ball to start the game would allow the other team to choose which goal to defend. Teams switch goals following the first and third quarters. If a down is in progress when a quarter ends, play continues until the down is completed.
National Academic League
In second quarter, five members of the buzzer team work as a team to answer lengthy questions. There is a back row of five reserve players, but this reserve used only at the discretion of the team coach, who can substitute any or all backup players for any or all active players. This quarter lasts ten minutes with 60 seconds (maximum) for each question. The questions are printed on a card, which is carried to the team by a player of the opposite team, the "runner". When the judge says "Drop", each runner drops the card down on the table. The time starts when the judge reads the question aloud. Players are allowed to talk with each other and write down answers, and collaborate. Although communication is a prime skill in second quarter, no other team member may speak after the captain has buzzed in. Each correct answer is worth three points.