Just a thought...forgive if it's already been discussed, this is a busy board! I have this theory on the whole school exit thing (and if there is a theories thread that this should go under, please move it, but...)
1) TH planned this out (I used to think it was an accident but I no longer do)
2) She told the teacher about an appointment to create an alibi of sorts, in that she
may have IMO told the teacher "Kyron has a doctor's appointment" knowing full well she gave her paperwork for a week later but giving her some time because they would think Kyron was with her that DAY for an appointment.
So then when the LE asks her about it, she can say 'well sure I told her he had a doctor's appointment, but I meant NEXT WEEK" and she had the paperwork to 'prove' what she said.
"Finster said Horman had told Kyron's teacher the day before that she was taking the boy to the doctor on Friday, June 11, and gave the teacher paperwork to fill out related to the appointment.
Finster said that when Kyron didn't show up at the bus the afternoon of June 4, Horman talked to the teacher who said she thought that Horman had taken Kyron to the doctor that day. Horman told Finster that the child's teacher was new, in her first year of teaching, and was hard of hearing in one ear. "She doesn't know if she understood her," Finster said."
http://www.oregonlive.com/portland/index.ssf/2010/06/friend_says_terry_moulton_horm.html
3) The classmate saw the SM leave the school alone because he did see SM leave alone. She simply told Kyron "Meet me around the side after you look at the electrical ______" and picked him up, or she had told him earlier, "Go to the car and I'll be right there" and he went and jumped in and waited.
I believe
IMO there HAVE been sightings after the second round of questionnaires and polygraph test that Kyron was seen running to the car, or in the car as it drove away, or something (this is PURELY speculative but would explain why DY and KH have really done an about face) but the LE isn't telling us and letting her spin her lies as much as she wants.
4) Whatever she did to that boy at this point, I have no idea but pray it's a balloon boy thing.
5) She thought she had all her bases covered by a) taking a picture of him, being seen with him and leaving 'alone' w/o him. Then, to go to the bus and act surprised was part of the plan because people would think anyone guilty wouldn't come back home, act relatively normal and even show up at the bus stop.
Whew - that's a bit long-winded to the SM seen in the school and the last one to see Kyron, but I think it's pretty logical. I just pray for this little boy's safe return.