My Own Little 'Three-nager' (except she's 5)

Today was back to school for WA.
For the last two weeks I've dreamt of this day, literally!
This school holidays hasn't been the best. I'm now the size of a rhino with baby number 3 so outings were pretty slim.
Instead we stayed at home (which is now my mothers house, until bub comes along) painted, played games, watched movies and relaxed.

But no matter what we did the kids just DIDNT get along. They fought, they didn't share, they pulled each other's hair, pinched, punched, slammed doors and just generally didn't get along.

I was so frustrated that they were being so unfriendly towards each other. Normally they get along pretty good so this was extra annoying! I was constantly separating them to play by themselves (the only times they played nicely was when they were at opposite ends of the house)

And then today! Back to school! I was so happy, the kids needed some time apart from each other, I needed a break and they were keen to go back to school.

My happiness was soon shattered though. Miss 5 came home with the great attitude she picks up from school. I don't know who it is or where it comes from but whoever Miss 5 is playing with has the worst manners. She comes home from school with her hands on hips, shouting, speaking like a snotty little snob and then when I asked her to please speak nicely to me she yells "fine I don't want to talk to you anyway" the friends that I know about all have beautiful manners, so I'm thinking there is another person she plays with that doesn't get a mention but obviously makes a big influence on her  attitude.

So what's worse? Two kids constantly fighting or one coming home from school with a worse attitude than most teenagers? You tell me!!

Does anyone else's daughter (or son) come home from school with a bad attitude? Do they pick up and copy some of the worst behaviours? Or are your kids personalities the same when at home as when they have been to school?
Usually Miss5 is a lot more pleasant...and then she goes to school and goes all 'psycho teenager' on me!!
Please tell me I'm not alone!!!