Near the end, when the twins come into the dance, Jean gets the attention of Michel and points them out. Then the two take off their guitars. In the next shot where Ally and Melanie are talking to Jeremy, the boys are doing the exact same thing.
When the twins are getting ready to leave Paris, Brigette is wearing a different dress than the one she's seen wearing in the next scene which is just outside the building a few minutes later.
When the twins are making a change in the plan for Jeremy to meet Brigette, it is seen that the "h" key is pressed. Yet in the text they type, "Luxembourg Garderns", there is no "h".
At the end of the movie, when the girls' grandfather says they can go to the dance, they rush out of the room saying they have to go get ready. Yet when they enter the dance, they are wearing the same outfits that they wore to his party.
When the girls are pressing their faces against the window in a locked car so Jeremy can't open it, you can clearly see an open window on the other side of the car, he could have unlocked the car himself.
When Michel was offering Ally and Melanie to go with him and Jean to see the real Paris. The words "We're so there." and "Let's go." were heard but Melanie and Ally are not saying these words as they leave the table.
When the flight itinerary is shown, the plane lands in a 'Paris' situated in Africa. France is an European country.
When Jeremy tears up the itinerary outside of the embassy, the boom mic can be seen swinging over the car in a reflection in the rear window.