Psychological Problems, Age vs Grade in Peel Schools

Hi
I am a new immigrant from Pakistan settled in Brampton two weeks ago. Back in Pakistan my two daughters (born 2003 and 2004) has completed grade 4 and grade 2 and were promoted to next grades in July 2011.(both of them had enrolled in school at the age of 2.5 years), both were studying in one of the best available school system in Pakistan (Beacon House School System) where both of them were position holders in their classes. Both of them have a very good communication as well as reading and writing skills in English.
The staff at 'Welcome Canada' has guided us to 'Ridgeview Elementary School' Brampton; where my daughters were enrolled in Grade 3 and 2 according to their age as per law of the 'Peel District School Board', my kids will have to again appear to the 'Welcome Canada' on Sep 20th, 2011, where an assessment will be made about their grades.
My both kids are very much disturbed, even became psychologically ill, due to their degradation. They feel that they are far much step ahead as compared to their classmates here, after attending the school for few days, and they should be in higher grades. And if this is not possible then we should return to Pakistan.

My question is
Is there any possibility, by appealing to 'Peel District School Board' or any other method/procedure, that my daughters can be enrolled in higher grades. Is the Age vs Grade law so rigid that kids will become psycologically ill. Is there no advantage for the kids with extra talents and intellect.

Please guide me