When searching the so-called haunted house on the hill. It is clearly evening because it is completely dark outside. There's no power in the building, so they need to use flashlights, but when Derek is clearing one of the rooms, sunlight is coming in from the outside, because of the thin white curtains. This is not from any vehicles out in front of the building. It's obviously sunlight. There are also shadows seen on the wall from the staircase because of the incoming sunlight.
When the BAU is addressing the police department, Reid is standing against the wall with his arms crossed. Immediately afterward, his hands are in his pockets and you see him crossing his arms again.
When Tracy, Henry and Simon get off the bus, Simon goes walking with Henry rather than towards his home with Tracy. School buses tend to leave children off close to their home, so this makes no sense that Tracy would be getting off the bus far enough away from her home that she would need to have a buddy for protection, especially considering Jeffrey says he knows a shortcut to help her get home quicker.
When Reid and Gideon are addressing starting a curfew (around 10:40), you can see the spike tape for the actors' marks on the floor.
At about 14:52 JJ says she has a niece the same age as the child she's speaking too. However, in later seasons we learn JJ's sister committed suicide when JJ was a child and no children were ever mentioned. There were no other indications the JJ had other siblings.