Continuity mistake: SPOILER: The boy, Roger, finds a glove in a secret drawer in Mr. Holmes' room. The glove is lying perfectly flat in the drawer. It had supposedly been there for years unknown to Mr. Holmes. Later, in a flashback scene, it shows Dr. Watson putting the glove in the drawer. When he puts the glove in the secret drawer, it is not laid flat in the drawer - it has an obvious upward bend in the glove. Since the glove had been in the drawer, untouched, for years, it should have still had that upward bend.
Suggested correction: Although we are only shown Watson putting the glove in the drawer once there is no reason to suggest he may not have looked at it again before he left for good. More compellingly, Watson placed the glove in the drawer whilst the bureau was in place in Holmes' quarters in London, and it was not discovered until a quarter of a century later having been moved at some point to Holmes' house in Sussex. This journey could also easily have displaced the gloves position to some degree. The weight of papers contained in the drawer above may have also aided in flattening the glove out over the years.
Factual error: The delivery van bringing gear for the walk has a 718 area code on it. That area code did not exist until 1984.
Continuity mistake: In the locker room scene after Tony injures his knee, Tony walks outside the room crying and he then throws his helmet against a wall, causing the chin strap to fall off onto the floor in front of the the doors. When the coach walks in through the door, the chin strap has disappeared. When the coach and Tony hug, look just behind the coach's right arm. You can see a quick glimpse of the chin strap back on the floor where it was before.
Revealing mistake: When Rachel has a red turban on and is supposed to be bald, you can see her hair under the turban.