16 year old stepson tattling/jealousy issues

I am at a loss, I have a 16 year old step son, and he is constantly tattling on my 8 year old son.  Problem is, my 8yo pretty much keeps to himself and does his own thing and doesn't bother anyone, until my step son and 12 year old daughter taunt him.  Then my stepson tattles on him, complains about him and then when he and my daughter get in trouble for taunting him in the first place, he tries to turn it around and say my son never gets in trouble.  My son doesn't bother with either of them until they do something to taunt him, i.e. my step son will take his video game and won't give it back, tells my son he needs to share, they will try to push their way into my son's room, etc., then my son gets upset.  My stepson then walks around saying my son is acting like a 2 year old when in fact it is him that is acting like a 2 year old.  We only have my step son every other weekend and one night a week for dinner.  

My son is the quiet, logical type.  He's very smart and likes to build things and do things that are mentally and tactically stimulating.  My step son is very lazy when it comes to school and things that are mentally stimulating.  

Any suggestions on how to handle this sort of behavior?

[margypops]

I am sorry this does happen a lot between step siblings and bio siblings, and can be the cause of a lot of anxiety for the child having to take this behavior. There is always an element of jealousy aswell, I am thinking your best bet here is for you and your son to get clever and beat them at their own game, how about he decides he isnt going to play the video games whilst they are visiting maybe he lost it, tell your son to stay out of his room as much as he can thereby giving them no ammnunition,is there a Dad around what does he say about the issue?Lastly talk to your son, they are obviously feeling left out in some way as their Dad is part of yours and his family , maybe some extra sweetness and light could work wonders even if your son doesnt feel like that .Good luck these situations arent easy ..