The episodes for this series were intentionally not broadcast in chronological order. Hence why at the end of episodes, the next announced episode number did not always match. Usually, Haruhi would announce it only to be corrected by Kyon. This leaves two different options of viewing: chronological order or broadcast order.
For the broadcast order/comparison between the two:
http://en.wikipedia.org/wiki/List_of_The_Melancholy_of_Haruhi_Suzumiya_episodes