Does anyone know what it takes to get your residence permit extended for a period of 6 months.

I have a residence permit through my employer for my entire family . But this is valid only until Jan 08. My contract ends in Jan 08 which means we have to leave the country. However is there a way i can extend it until june 08 so my sons can finish the school year. My employer will not do this extension for me.

Will a bank statement showing proof of financial status and health insurance be enough to get me through. I am a non EU citizen

Any suggestions on this process ?