Jørgen Jakob Friis
The easy thing would be to ban them from class, but I really really believe that they need it more than the rest and that we should do our best to handle them in a good way.
You WILL get frustrated with certain kids. Don't give up on them. Down the road you may realize that it made a huge difference for them.
The neat thing about teaching kids is that for some of them, aikido will be the experience that pushes them in a better direction. Getting a better direction at such a young age makes a huge difference in the final outcome.