How much notice should I give?

Hi,
I've been working for my host family for over 7 weeks now, they have been so lovely to me and have tried to help me settle in as much as possible. However, I'm finding it very difficult to settle in, there are no other au pairs in the surrounding area. (I have tried every website!) I don't think this job is for me.
I have made my decision to leave. I'd like to know how much notice I should give - I haven't signed a contract and haven't gone through any agencies. I have said I can stay until December but would ideally like to leave within a month. Is this enough time?
I would really like some advice from some host families.
Thanks
Maisie

 I am with Cultural Care Au

 I am with Cultural Care Au Pair. When an au pair goes into transition, the customary notice is two weeks. During that time, the company looks for a new family for the au pair and a new au pair for the family. Since you are not with an agency, you are in a little bit of a different situation, but I would give at least two weeks notice so that your family can look for alternative childcare. Cultural Care has a pretty wide network of support out there, if you'd like to email me offline, I would be happy to see if we have some au pairs in the area where you are located to see if you can make some friends. We may have a local coordinator near you, who can help you get connected. I know you have said you really like your host family, so if it is a matter of finding friends, and adjusting, there are still some options for you there. Also, have you tried registering for classes at school? That is another great way to make friends. You can reach me offline at tracy.cota@lcc.culturalcare.com or call me at 310-283-3521.

A little late, but...

Since you are not with an agency, I will go ahead and say that you should be as kind as you can to this family (who you even acknowledge has tried to help your adjustment).  If you are making plans to leave in 4 weeks, then give them 4 weeks notice.
 
Yes, when the family is with an agency it tends to be a bit easier for them to find a replacement (we are with an agency - NOT Cultural Care), but since they will be starting from scratch and not have the resources of an agency to help filter and track down possible applicants, then be fair and give them as much notice as you possibly can.  I am sure this reply no longer applies to you, but just in case someone else checks it for the same type of reason and does not want to feel like the only way out is to get both themselves and the HF into a massive contract with a hard-selling agency.  The right answer is to approach them with the respect you want them to approach you, just as you would with any job that is not an AP one.