Continuity mistake: When the guidance counselor is addressing the community members, Reid is standing against the wall with his arms crossed, and then immediately after his hands are in his pockets, and you see him crossing his arms.
Visible crew/equipment: When James Charles, the guidance counselor, says, "It could be someone you know, or it could be a stranger you pass at the grocery store," the actors' red T-marks are visible on the floor at Reid's and Gideon's feet. Then when Charles continues to say, "gathering information on the case," we can also see the actor's white T-mark beside the counselor's feet, where he will stand after he introduces Gideon.
Continuity mistake: When the pregnant lady came in with her child saying her 8 year old Matthew was missing, JJ sits her down and says she has a niece who is 8. We later learn that JJ's only sibling was her sister who committed suicide and who didn't have any children.
Answer: "The Boogeyman", s02e06. Spoiler alert: The kid is Jeffrey Charles and at that point he had already killed 3 other kids. Jefferey basically hated and resented other kids after his mother abandoned him and his father spent a lot of time with other children because of her job. Jeffery would lure kids Into the Woods and then beat them to death with his bat just because of hate, no particular "reason." The scene you're describing, Jefferey agrees to walk Tracy home when her "buddy" leaves her (at this point the FBI announced there's a serial killer on the loose and kids should walk with a buddy). Jeffrey gets mad at Tracy for walking too slow and for complaining, and he takes a swing at her, causing her to flee Into the Woods and have Jeffery chase her.
Bishop73