Zurich is probably one of the easiest cities in Switzerland to integrate your kids into the school system. There is a huge number of foreigners here and the schools are well geared to coping with kids lacking the language.

They tend to teach in standard German but the kids will speak together in the local dialect.

In the meantime, if you can get hold of any CDs or DVDs of kids programmes in German, start exposing your kids to the language now and it won't seem so alien to them when they arrive.

You can get many of the recognisably "British favourites" (Bob the Builder, Fireman Sam, Postman Pat) in German from Amazon.

For the older child, you could get some of the kids' films such as Nemo, Monsters Inc., etc, in German and let him/her watch them for a similar effect.

Your kids are still within the age limit which they reckon they can pick up the language relatively quickly and a quick search through the forum will pick up lots of stories of parents whose kids were fluent within a matter of months.

Of course there are always people who had a bad experience but, after living here almost 10 years, most of the parents I know have only had good experiences.

Good luck.