Other mistake: The video stream displayed in the night sky showing which tributes have died after the first day does not add up correctly. They display in district order. We see the start, the girl from three (so the boy is still alive), and the boy from four with no breaks. Then they break away to show Katniss and the control room, after which they continuously show the boy and girl from seven, the boy from eight (so the girl is still alive), the girl from nine (so the boy is still alive), and then fade to the end. We know that Foxface, the girl from five, dies later in the movie. Even if we assume that during the portion not shown, the girl from four, the boy from five, and both tributes from six are dead, that's only a total of ten. Thirteen are supposed to be dead at that point in the movie. (01:16:20)
Continuity mistake: In the shot where Katniss walks up the steps after volunteering to replace Primrose, Effie's fingers are waving her forward, but on the giant screen visible in the background, her hand is still. (00:16:05)
Other mistake: When Katniss retrieves the bow and arrows from Glimmer, there are six arrows in the quiver. She probably recovered the two arrows that Glimmer and Cato shot at her in the tree, bringing the total to eight. Katniss did not recover the two arrows she used to blow up the Careers' supplies, bringing her total down to six. She probably recovered the arrow used to kill Marvel, but did not recover the two arrows she shot at Clove, bringing her total to five. She did not recover the arrow used to kill the muttation, nor did she recover the two arrows used on Cato, meaning that at the end of the Games, she should only have had two arrows remaining. However, at the end, she still had about half a dozen arrows remaining.
Revealing mistake: When Katniss is blown back from the explosion, her stunt person is visible. This can be proven because the stuntperson's skin tone is different and her hair is not in a braid. It is in a ponytail. Wires can also be seen pulling her to give the illusion that she was blown back from the explosion. (01:33:00)
Continuity mistake: In the scene where Katniss uses the remote to change the scene in her bedroom window in the Capitol, her hair starts out stringy (having just been taken out of the braids she wore in the opening ceremony) and changes to full and beautiful and switches positions around her face and shoulders as the scene progresses. (00:34:10)
Other mistake: When Katniss, Peeta, and Cato are on top of the Cornucopia (after being chased by the muttations), near the end of the film, Katniss aims an arrow at Cato while having Peeta in a headlock. Katniss has her arrow fletchings on backwards. This would prevent her from shooting straight. (02:00:25)
Character mistake: When Katniss is trying to destroy the supply pile, we see a close up of her drawing back on the her bow. We see she has the arrow to the left of the grip, meaning the fletchings (feathers at the end by the string) have to be facing to the left. Otherwise the fletchings will hit the grip, rip off, and make the arrow unstable in flight and go completely off course. However, the fletchings are are facing to the right and so will hit the grip. Any archer or anyone who is skilled with a bow would know this. (01:32:45)
Other mistake: We are told that there are a boy and a girl tribute from each of the 12 districts, making a total of 24 tributes. However, in the scene when Katniss is figuring out the Cornucopia stockpile is mined, the camera sweeps round dug-up earth next to all of the launch pedestals - yet only 20 pedestals can be counted. This can also be seen from an aerial shot in the same scene.
Continuity mistake: When Katniss is saying goodbye to Gale, just before she is taken away for the games, there is a small curl of hair hanging down the left side of her neck that can be seen in all the shots when the camera is behind her. Whenever the camera angle changes to a face shot, the curl of hair disappears.
Continuity mistake: In the scene where Katniss is being interviewed by Caesar on stage before the games, her hair is securely up kept in the back. As she is twirling to show off the flames, you notice her hair has come undone a bit and is drooping in the back. By the end of her twirling, her hair has returned to its previous secure up-do. By the end of the interview, her hair is sagging once again in the back. Then, returning backstage with Haymitch and Effie, her hair has returned to being secure and neat. (00:56:20)