I'm at a loss

My son has, up until now, been the easiest, most well behaved child my entire family has ever seen.  Yeah he has a few moments, all kids do, but his 'moments' are mild compared other kids. 

Until now.

I was warned by my MIL that my BIL was the sweetest little boy until he went to school, then he came home with an attitude that never left.  I was warned that he'd get snippy, that he'd test his boundaries, etc.  I prepared myself, but I prepared myself for the worst I'd seen him be.

And that is SOOOOO not what he's becoming.

He fights us over everything.  E.V.E.R.Y.T.H.I.N.G.  Like brushing his teeth or buttoning his damn pants or even where he's playing and where Jocelyn isn't allowed to go. 

His teacher has been telling us how he's not listening and misbehaving more.  I'm afraid she thinks we're not doing anything about it, because he's getting worse.  But we are.

We put him in time-out, we take his toys away, we don't let him have a treat after dinner and if all else fails he gets a swat.  And none of it is working.

Consistency my ass Mr. Experts.  We are doing the same things we always have, except about every 10 minutes instead of every 10 days.  We don't let him get away with things in the hopes that it will just go away.  If we say this is going to happen if you don't mind, this happens.  We're consistent folks, and we're seeing zero improvement.

In fact we're seeing a progressive backslide into misbehaving, and it's almost 24/7 at this point.

Except at my parents..which I'm 100% positive is where he gets away with his attitude and baby talk when we're not there.

Today has been stupid, just down right stuuppiiidd.   He got a sad face at school today but refused to tell me why.  That means no Rockband, which is almost as harsh as a swat but he cannot continue to act up at school.  He says he can't remember, which anyone who has met this kid will tell you he remembers everything.  I can safely say he's a liar and a fat mouth and that he knows he just doesn't want to tell me.  I was proven right after Bo got home because he said "I don't know what I did to get the yellow ticket.  There were so many things I don't know which one is why I got the ticket".  And that is all he will tell us.

When we sat down to eat, he was all excited and told us how much he liked dinner.  Then a few minutes later he didn't like it and didn't want to eat anymore.  Ooook, we got it out of him that he wanted to play instead.  We informed him, that he either stopped his attitude (he was crying and yelling at us for being mean) and ate his dinner or he'd go to bed.  Bo even got him a fruit cup but after a few bites he realized he wouldn't get out of eating his dinner, he started his fit again.  Bo got up to take him to his room and that's when he said "I hate my parents".

Oh yeah.  Thank you, whatever child at school that taught him that.  Come to my house for a while and you'll be glad you don't have me as a mom for teaching my child this shit.  I love my kids, I'm nice to my kids, you I don't have any nice for, since you have corrupted my son.

We sent him to his room where he screamed for 10 minutes straight.  Bo went to talk to him, since he's better at talking to him than I am, and got him to apologize.  Now we HATE sending him to bed hungry, we don't agree with that (no offense to those that do this, it's just not our thing) so we gave him another chance to eat his dinner.  Two bites of two things and he's done.  That's it.  But no he started throwing a fit that he wasn't hungry and when asked if he'd rather go to bed instead he said yes.

OMG I need a fucking drink and we have no liquor.

I'm totally not joking by saying that I'm tempted to call Super Nanny.  I want this to stop now before this gets any worse.  BEFORE it sneaks its way over to my already attitude filled daughter.

Any ideas?? I'll try anything at this point.