Continuity mistake: When Adam is in the park watching for roller bladers to miss the turn and crash, he places a stick in the path and the 3rd skater trips on it. When the skater falls, he ends up in the water and after he strikes the water you can see that the large flat rock on his left begins to move and bob around in the wake of the water.
Continuity mistake: When Sonny, Julian, and the two gay guys are in the park eating, the gay guy on the left (in the grey sweatshirt) is holding a bag of potato chips in his lap. First you can see the front of the bag, then the camera cuts to another shot, and when it returns, the back of the bag shows. This occurs many times in this scene.
Continuity mistake: When Sonny is giving Julian a bath, in the shots where Julian is closest to the camera, you can see a wide gap between the bath and the camera and even the side of the bath tub, as if it's in the middle of the room. In the shots behind Sonny, the bath is right next to a brick wall.