Ever wonder just what the coaches are looking at when the call a play either up in the press box or down on the field? I was able to look at a blank copy of a form that USC uses at a coaching clinic and ask a few questions. It is similar to just about every game plan and play calling sheet used from high school on up to the professional level. The format is no secret it is the content that of course is protected and varies from week to week depending upon the opponent. The play calling process and this game plan sheet is the end result of a hard week (or more) of work by the coaching staff. The contents are created by the entire staff in a series of meetings during the week and organized by the offensive coordinator - hence the term "coordinator". The process is explained in an article by former Miami Hurrican and current University of Mississippi offensive coordinator Dan Werner that is summarized on this site - Developing a Game Plan. Once the game plan is done the results are compiled onto some forms that usually look like these below. Each coach does it slightly differently and some use cards instead of paper, etc. During the game they use the form as a way to organize the plays the coaching staff identified as appropriate for the game and practiced during the week.
On one side will be the different types of plays the team plans to run in the game listed by situation. Plays fall into situations for the coaching staff and they group them according to 1st and 10, 2nd and short, 2nd and medium, 2nd and long, etc. In addition each team usually scripts its first 15 or so plays like Bill Walsh advocated when he was with the San Francisco 49ers. The reason for the scripting? It is to see how the defense reacts against certain plays and formations early in the game. The coaches are probing to see if the opponent stays with its tendencies identified on film and where that implies the offense should attack. For example how does the defensive front change, or how does the secondary coverage change in response to certain formations and alignments. This helps "adjust" the plan once the first series or two is over. Other adjustments are of course made at half time and throughout the course of the game as needed.
The other side of the game plan will look something like as follows:
This side is for most special situations in addition to the base offense listed on the other sheet. On this form are the special calls for when the offense is in the "rip it" zone or inside the opponents 40 yard line or "backed up" inside the twenty yard line. It also lists special "shots" or "deep play action" pass plays for when there is an opportunity to throw the ball downfield. It also lists a variety of plays that might be needed in any game such as naked bootleg rollouts by the QB, screens or special goal line plays, etc. Each is considered a different category of plays for the offense to execute. In addition is of course the hurry up 2 minute offense, the slow down 4 minute offense, as well as special plays to beat Cover 2 secondary schemes or whatever secondary defense the opponent is playing that week.
The average college football game has anywhere from 65-75 plays on offense for each team. There may be as many as 100 different plays listed on this sheet but that figure is misleading. The average team probaby runs the ball about half the time meaning there might be 35 run plays and 35 pass plays in a game for example. In order to run the ball 35 times most teams probably only have about 6 to 8 different run plays at most. A subset of those will be used in the game depending upon the scouting reports and what works well during the game. On the passing side there are only nine or ten different receiver routes on a standard passing tree. The coaches combine the routes to form passing patterns but in reality it is all combinations of the same basic routes.
All good coaches at the college and NFL level do a good job of making similar plays look different. Former offensive coordinator Norm Chow once commented that in all his years at BYU for example they had four basic run plays and about eight to twelve basic pass plays each week. He made it look like more than that by calling the same play from different formations, altering the personnel, and using motion. In reality coaches will all tell you the game is far more about execution and players than about "play calling". But don't tell the average fan...it would only spoil their fun and normal routine of criticizing the play calling when things break down.