Character mistake: In a conference with Crockett and Bowie, Travis states that Fannin in Goliad is preparing to relieve the Alamo and will be ready to "march south by the end of the week." Goliad is 90 miles south of San Antonio. To relieve the Alamo, Fannin would need to march north.
Character mistake: In one scene, one of the people suggests that Danny Ocean should run for President, and the first plan of action was to repeal the "13th and 20th" Amendments to the constitution, allowing women to lose the vote and go back into slavery. The 20th Amendment has nothing to do with women's right of voting, that is the 19th Amendment. If the 20th Amendment were repealed, the President would again take office on March 4th in the year following the election.
Character mistake: At the end, Professor Challenger misidentifies the dinosaur in the boiling water as a T-Rex. Its arms are too long, and it sports horns. It is much more likely a carnotaur. This area being a forte of his, I doubt Professor Challenger would make this mistake.
Character mistake: When Dean Martin desribes his writer's block to Judy Holiday, she says that she keeps sharpening his Ticonderoga pencil until there's nothing left but the "Ti," but in fact what would be left on a little nib is the "ga."
Character mistake: The protagonist at the beginning of the movie is cleaning his own apartment when Kirkeby returns for the missing galoshes of his lady companion. Kirkeby searches a chair, looking also down on the floor to the side of it, turns around and looks up the other one and then back towards the starting point. He picks the galoshes a few seconds later finding them in a spot where he supposedly has looked already almost all the time (the actor just pretended to look). (00:06:40)