Continuity mistake: In S1 they became the 2007 state champions. In S2 they were referred to as the 2006 state champions.
Continuity mistake: In season one Assistant Principal Trucks makes an announcement with a woman's voice that Voodoo was deemed eligible. In future episodes Assistant Principal Trucks is a man.
Continuity mistake: As Coach Taylor exits his front door, he is holding his ball cap, sunglasses, and some papers in his right hand. The hat is dangling on the left, and the sunglasses on the right. In a sudden shift to a wider shot, we now see the sunglasses and hat have changed position - sunglasses on the left, hat on the right. (00:38:53)
Continuity mistake: Coach Taylor is driving Tami to the airport. With each change in exterior shot, the window is rolled down on the side of the car nearest the camera and rolled up on the "far" window. They magically disappear and reappear. Also, there is little to no continuity in the exterior locations as they roll along and shift shots; moving from residential to industrial to open highway and back with no transition. (00:19:50 - 00:20:48)
Factual error: They are supposed to be in Dallas for state. Eric and Tami go out on the balcony to talk, and they are in Austin with the Frost Bank Town in the skyline.
Injury List - S4-E11
Continuity mistake: Coach Taylor gets home from practice and talks to Tami. Tami explains she is not getting fired and Coach Taylor says that he'll go get the wine. Next scene he's back at the school talking to Buddy. (00:24:28 - 00:26:12)