Deliberate mistake: I have participated in several amateur karate tournaments over the years and I have yet to see one that is full contact without any protective equipment whatsoever, especially one in which all of the participants are minors. All of the contestants should at a minimum have had mouth guards, gloves and foot pads.
Deliberate mistake: At the end of the film, when Alex, Maggie and Grig take off in the Gunstar, the crowd of trailer park residents watching them leave backs into the covered portion of the restaurant, right next to the 'Starfighter' game cabinet, which is readily visible in the shot. Mrs. Rogan then wonders where her younger son, Louis, is. The shot changes to show Louis pulling a bench up to the 'Starfighter' game to play it as dust from the Gunstar liftoff kicks up next to him while he watches it fly. Yet the crowd is nowhere to be seen in the shot of Louis playing the game despite everyone being huddled right next to it on the patio (his mother was standing next to it and should be able to see him). Given the proximity of the crowd to the game a moment earlier, Louis wouldn't be able to play it, let alone put a bench next to it. It's clear the filmmakers chose the image of the younger kid aspiring to be like his brother by playing the game over the logic of where the game was in relation to the crowd.