I live in the Portland area, and I have been following Kyron's disappearance since the first evening he was reported missing. I have been to Skyline School several times, and I have developed my own possible theory for Kyron's disappearance. Frst of all, I am 100% convinced that Terri Horman orchestrated the whole thing.
Terri arrived at Skyline School in the Horman truck with Kyron and Kiara at the time she stated. One thing about pathological liars is that they tend to stick as close to the truth as possible and deceive people only as much as is necessary to get away with their scam. It is easier for them to keep eveything straight that way. I also feel that it is highly probable that Terri Horman is a narcissistic sociopath, and her entire adult life has been one of lying and scheming. She fits the profile very well.
Terri would have parked in the parking lot immediately accessible when turning into the Skyline school property. I don't believe that she parked in the back of the buildings. I suspect that she wanted her arrival with the children to be noticed as much as possible.
This time correlates very closely to one of the times Terri Horman claimed to have left Kyron in the hallway near his classroom at 8:45 am. Therefore, I feel that she walked out of the school building around 8:30 am with Kiara to the truck, hoping to be seen walking without Kyron to her vehicle and leaving the school grounds. I believe that Terri told Kyron that she had to attend to Kiara for some reason, and for Kyron to wait for her at the door of the building below his classroom so that she could take him to his doctor's appointment. Then, Terri left the school building with Kiara, drove the truck out of the Skyline School parking lot, briefly down Skyline Blvd., and then backed into the access road. Terri probably put Kiara into her carseat and walked back along the access road to meet Kyron at the side exit door of his school. Once they walked down the stairs to the access road, they would be out of view. Alternatively, Terri may have instructed Kyron to meet her at the truck parked below the school on the access road so that she could take him to his doctor's appointment. I believe that Terri did make a doctor's appointment for June 11, 2010, but that she deliberately told the teacher and Kyron that the appointment was scheduled for June 4, 2010. She would have given Kyron detailed instructions to walk out the door and down the steps leading tothe access road next to the soccer field. Due to the science fair activities, and the distractions of other students being dropped off by the buses, it is unlikely that Kyron would be noticed at all leaving the school through the before mentioned door and down the steps.