Factual error: The scoreboard at Shotwell Stadium in Abilene shown during the Abilene High game was inaccurate for several reasons. That particular scoreboard was not installed until somewhere around 2003, a much older and less technologically advanced one was in existence at the time of the movie. Also, there are problems with the major sponsors on the scoreboard. Both are real businesses, but the Ambassador was known as Embassy Suites until the late 1990's, and Lawrence Hall Chevrolet did not use that logo that far back.
Factual error: When the coach and his family are leaving Wal-Mart , we get to see the new color scheme for Wal-Mart stores. In the '80's Wal-Mart store signs and exteriors were painted in brown and white. This sign is blue and white with red and blue stripes down the building. This is obviously a modern Wal-Mart building.
Factual error: In the state championship game it is 4th and inches for Carter. Permian stops the play and tackles the runner around the 37 yard line. We see this with the two "X"s on the field for kickoffs which are at the 35 and 40 yard lines. We also see the 30 yard line that he is hit at before being backed up. The announcer says 1st and 10 from the 25. That is the wrong spot for the ball.