Since no one has really taken the time to debunk this here you go:
First off I want to note - the main contributor of information in this video and around this conspiracy is Alex Jones. He is, in my opinion, a paranoid nutjob, as was pretty evident by his CNN interview - seriously skip to 3 minutes in and tell me this guy is sane. (My intent here is not ad hominem, just wanted to give some context as to the presenters of these "facts" and their origins) Now that that's out of the way let's look at the content of the video...
Theory 1: The first thing the video tries to allege is that there is a second shooter. They love to grab early media footage and then use that as "evidence" of their claims, as if the media's first reporting is somehow golden. Odd that conspiracy theorists distrust the media, then turn around and use its raw reporting claims as evidence. Anyway, you can easily google and figure out who the guy in the woods was.
https://www.youtube.com/watch?feature=player_embedded&v=Y6C2YmOLWnMHe is the father of a student there and the athletic director at the highschool. He was on his way to the school to help make gingerbread houses with 1st graders when he heard the shots. He was unarmed, arrested, detained, questioned, and let go. The story of the guy in the woods was a dead end, so the media dropped it. That is the problem with the 24 hour news cycle, they will report any lead they get before sorting out facts. However, this is hardly evidence of a conspiracy.
The video even makes the ridiculous claim that since the guy was sitting in the FRONT of the police car, that he must have some "crazy" credentials. Yeah, what is more likely...that this guy was a concerned father or that he was a man with some "crazy" credentials on a black ops mission to shoot up a school but he just didn't have the skills to properly vacate, and so he ended up getting himself captured by lowly local law enforcement, AND broadcast on national tv, potentially exposing his super secret black op? C'mon.
Theory 2: The gun discrepancy. This can be chalked up to contradictory reporting, which is going to happen when the media competes with itself to be the first one to break any new details. There have already been articles clearing up the discrepancies:
http://edition.cnn.com/2012/12/18/us/connecticut-lanza-guns/index.htmlTheory 3: The nurse is fake and does not exist. This is completely false, and has been debunked with evidence:
https://www.youtube.com/watch?v=r61PvN4U3x0Theory 4: The laughing/crying father. This means absolutely nothing. No one can judge how a father copes with the loss of his daughter, and it's offensive that people are criticizing him for it. I have been to several funerals, I have witnessed family members and friends switch in and out of laughter and tears. They think of fond memories of the one they lost, they tell stories, they laugh, and they cry. People grieve in different ways. To me it does not seem right to criticize his reaction here, and it's not evidence of a conspiracy.
Theory 5: Emillie Parker is not dead. This is the most absurd thing I have seen so far in the video. The video alleges not only that the girl is not dead, but that the parents were so stupid they brought out the wrong sister for the photo op. What? Do people honestly believe that?
https://www.youtube.com/watch?v=DTaC580hfPo It's a picture of her sister. Obviously. They look alike because, you know, they're sister's. This guy uses the same photoshop trick as the conspiracy video and gets the same effect. Check out their noses in this picture for further evidence:
http://i.imgur.com/iSuf4.jpgTheory 6: One piece of footage of the crime scene does not show many ambulances and shows no children. The author claims this means this was all staged. He goes on to say that only one ambulance was there the whole time and they quickly blocked off all exits. The problem with this is twofold. Firstly, there are several pictures of multiple ambulances (here are a few):
http://imgur.com/hb6kZ,XGWSd#1http://www.politico.com/story/2012/12/connecticut-school-shooting-official-says-gunman-killed-85094.htmlSecondly, this footage that the videos author is commenting on looks to be taken well after the shooting took place, which easily explains why there aren't a bunch of ambulances around and no one is panicking anymore. More things taken out of context because they fit the authors narrative.
Theory 7: Time stamps on the webpage set up for donations state the page was created before the shootings took place. Google search results do not always accurately reflect the date the content was published. Example) Here is a date restrictive search of sandy hook, listing all articles that appear to be published before the shooting took place. Well shit, according to google this there are articles and videos from these dates talking about the shooting: Jan 14, 2012 , Jun 19, 2012 , Sept 16, 2012 ..well before the shooting took place. Debunked.
Addition: People keep bringing up the facebook page that was made prior to the shooting. The creator of the page said they had made an unrelated page previously, it had no fans in it. After the shootings took place, she renamed the page to be a memorial for one of the victims. This changed the URL, but kept the original creation date of the group. Many claim this is not possible or this is not how facebook works. Here is proof that it is:
http://imgur.com/a/U6wWHTheory 8: There was a planned FEMA meeting scheduled 20 minutes from the time of the shooting which helped slow down the response time of first responders.(Added due to popular demand). I went to the emergency services website for CT to investigate this. This class is offered regularly. It was offered on 11/17, 11/27, 12/3, 12/6, 12/14, and 12/17. In fact, digging a little deeper you can see they have had training classes like these for a long time, such as this one way back on 4/2/2012 called Emergency Planning for Schools (2 day course):
http://www.ct.gov/demhs/ical/eventDetail_page.asp?date_ID=CACBCCCDCE83CDCACAThese tragedies have been happening for awhile, and so has training people to respond to them. Debunked.
Other stuff: The people that made this video clearly have their own agenda, which is why they keep bringing up 9/11 and the London bombings (two completely unrelated events). Any time a large, tragic event occurs, many of these conspiracy theorists do their best to gather all of the media reports, then pick and choose to take the media out of context and create their own crazy conspiracy driven narrative for the events that took place. If you are skeptical of this video, you should be. It's crap.