Hello. I recently started investigating through internet several missing persons cases and this is one of the most bizzare and difficult cases i've met (due to the lack of any shred of evidence). From what I' ve read on Jason's case only 2 scenarios seem plausible:
1) Criminal activity. Α serial killer or kidnappers. If it was a serial killer he probably had the experience to carry out his crime with scientific accuracy, knowing how to lure someone into his car or residence and then dispose the body without leaving traces. If it was an abduction case then the abductors could have led Jason to their vehicle threatening him with a gun. They may had no intention to kill him initially but this could happen accidentaly in the ensuing fight with Jason or during their try to gag him (asphyxiation). Then they could easily move the body away from the area and hide it in a very remote place making it extremely difficult to locate it.
2) Death by accident inside
a house nearby and cover-up. If this is the case i have thought of some realistic scenarios which I'm going to share.
a) Perhaps during his walk to the school someone invited him in his house to assist him with some technical work. Jason could have died there somehow (e.g. hit by electricity, falling from a ladder etc) and the owner hide the body in his cellar (or somewhere in his property) to avoid legal consequences.
b) While Jason was walking towards the meeting point with his co-worker he had a fight with other teenagers from a nearby house. Maybe they mocked him or insulted him for some reason (prank) and Jason being infuriated entered their yard/garden to respond. During the fight Jason was accidentaly killed (e.g. wounded by a knife and severe bleeding, a blow on the head which could lead to tongue swallowing and death if not given the appropriate first aid). The panicked teenagers hide temporarily the body in the house (if the fight took place behind a fence it could not be seen by neighbours) and later their parents (they may were at their job during the fight which took place in the morning of course) assisted furthermore with the body disposal. It is not impossible for parents to participate in covering a fatal accident caused by their children in order to save them from imprisonment. Their love for their children prevails over their remorse for a stranger victim even if he is also the child of other parents.
About the last scenario we had a case here in Greece where a child was accidentaly killed by other children of 11-13 years old after bullying and the authorities convicted not only the children but some of their parents and a grandfather who seemed to cover up things. The body has yet to be found
http://news.bbc.co.uk/2/hi/europe/5222512.stm
So it's not impossible for parents to cover and even support criminal actions of their children.
I just wonder if police has searched all the houses from Jason's house to the Benson High School. Did they have warrant to investigate inside the houses? Also, they should check which of the householders between Jason house and the Benson High Scool owns further properties (country houses, farms, fields etc). Another case we had in Greece was that of a teenager who had been murdered by his mother and stepfather and eventually his body was found buried in the stepfather's farm. So, secondary properties may seem important if there are any suspects in Jason's neighbourhood.
Of course I am not an expert and my scenarios may have already been investigated thorougly by police. I just want the case to be solved as any other missing person case and the families of missing people to find peace. But because police investigators are humans and humans make mistakes or may miss something that another person brings to attention, I think that any alternative or uncommon theory on Jason's case must be presented and taken into consideration.