In the café, Rachel hands Haley her purse, but when Nathan and Haley walk out of the café, Haley has no purse with her.
At the end of the episode 409, Some You Give Away, the paramedics are doing CPR on Lucus. The paramedic is doing compressions on Lucus's abdomen, instead of his chest to keep his heart pumping.
Nathan tells Lucas he can't change anything because he only plays 15 minutes a game. High school basketball games last 32 minutes. So with Lucas playing almost half the game he can make a huge impact on the outcome of the game.
When Keith is guiding Lucas in his dreams and onto the murder scene, part of the open set is visible right after Lucas asks, "Why are we in the high school?"
When Deb wakes up in the rehab center, the nurse has turned on Tree Hill's Championship game, but the game actually on TV is an Iowa State Cyclones Basketball game. The logos on the floor are completely different.
Tree Hill is in the state championship game and they are playing the game at North Carolina State Wolfpack basketball arena. Then in one cut scene, the basketball arena shows, but its not NC State's, it is the Iowa State Cyclones arena.
At one point in Mouth's commentary, he says time is running out in the 3rd period. Basketball has quarters, not periods. No one who wants to be a sports reporter like Mouth does would make this mistake.