Continuity mistake: The kids are in a circle on the living room floor. They're spaced well apart from each other in some shots but right next to each other in others; in particular Greg and Marcia, and Bobby and Cindy. (00:19:00)
Other mistake: When Jan finds the picture of her Aunt Jenny, we see a close-up of the picture with her hand holding it. She then passes it to Carol - and the same shot of the picture with the hand is shown again. (00:02:10)
Answer: The dangling bracelet was used for dramatic purposes - to keep the audience on edge.